[dna-commits] DNA SVN: r497 - in trunk: docs/gettingstarted and 6 other directories.

Author: rhauch Date: 2008-09-04 13:44:52 -0400 (Thu, 04 Sep 2008) New Revision: 497 Added: trunk/docs/gettingstarted/src/ trunk/docs/gettingstarted/src/main/ trunk/docs/gettingstarted/src/main/docbook/ trunk/docs/gettingstarted/src/main/docbook/en-US/ trunk/docs/gettingstarted/src/main/docbook/en-US/Getting_Started.xml trunk/docs/gettingstarted/src/main/docbook/en-US/content/ trunk/docs/gettingstarted/src/main/docbook/en-US/content/author_group.xml trunk/docs/gettingstarted/src/main/docbook/en-US/content/custom_sequencers.xml trunk/docs/gettingstarted/src/main/docbook/en-US/content/downloading_and_running.xml trunk/docs/gettingstarted/src/main/docbook/en-US/content/future.xml trunk/docs/gettingstarted/src/main/docbook/en-US/content/introduction.xml trunk/docs/gettingstarted/src/main/docbook/en-US/content/legal_notice.xml trunk/docs/gettingstarted/src/main/docbook/en-US/content/preface.xml trunk/docs/gettingstarted/src/main/docbook/en-US/content/understanding_dna.xml trunk/docs/gettingstarted/src/main/docbook/en-US/content/using_dna.xml trunk/docs/gettingstarted/src/main/docbook/en-US/images/ trunk/docs/gettingstarted/src/main/docbook/en-US/images/dna-architecture.png trunk/docs/gettingstarted/src/main/docbook/en-US/images/dna-logo.png trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-cli-client.png trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-search-with-mp3.png trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-search.png trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-search2.png trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-statistics.png trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-statistics2.png trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-upload.png trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-upload2.png Removed: trunk/docs/gettingstarted/en/ Modified: trunk/build/assembly/dist.xml trunk/docs/gettingstarted/pom.xml Log: Restructured the Getting Started document to use the newer JBoss.org styles, including code formatting Modified: trunk/build/assembly/dist.xml =================================================================== --- trunk/build/assembly/dist.xml 2008-09-04 14:34:21 UTC (rev 496) +++ trunk/build/assembly/dist.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -30,7 +30,7 @@ <!-- Gather into the distribution the Getting Started document --> - <directory>docs/gettingstarted/target/docbook</directory> + <directory>docs/gettingstarted/target/docbook/publish/en-US</directory> <outputDirectory>manuals/gettingstarted</outputDirectory> </fileSet> </fileSets> Modified: trunk/docs/gettingstarted/pom.xml =================================================================== --- trunk/docs/gettingstarted/pom.xml 2008-09-04 14:34:21 UTC (rev 496) +++ trunk/docs/gettingstarted/pom.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -1,17 +1,79 @@ -<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> - - <modelVersion>4.0.0</modelVersion> - - <parent> - <groupId>org.jboss</groupId> - <artifactId>documentation</artifactId> - <version>1.0</version> - </parent> - - <groupId>org.jboss.dna</groupId> - <artifactId>getting-started-${translation}</artifactId> - <version>0.2-SNAPSHOT</version> - <packaging>jdocbook</packaging> - <name>JBoss DNA Getting Started Document (${translation})</name> - +<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" + xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> + <modelVersion>4.0.0</modelVersion> + <!-- + parent> <groupId>org.jboss</groupId> <artifactId>documentation</artifactId> <version>1.0</version> </parent + --> + <groupId>org.jboss.dna</groupId> + <artifactId>getting-started-en</artifactId> + <version>0.2-SNAPSHOT</version> + <packaging>jdocbook</packaging> + <name>JBoss DNA Getting Started manual</name> + <description>The JBoss DNA Getting Started manual</description> + <build> + <plugins> + <plugin> + <groupId>org.jboss.maven.plugins</groupId> + <artifactId>maven-jdocbook-plugin</artifactId> + <version>2.1.2</version> + <extensions>true</extensions> + <dependencies> + <!-- + <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-jdocbook-style</artifactId> + <version>1.0.2</version> <type>jdocbook-style</type> </dependency> + --> + <dependency> + <groupId>org.jboss</groupId> + <artifactId>jbossorg-docbook-xslt</artifactId> + <version>1.1.0.Beta1</version> + </dependency> + <dependency> + <groupId>org.jboss</groupId> + <artifactId>jbossorg-jdocbook-style</artifactId> + <version>1.1.0.Beta1</version> + <type>jdocbook-style</type> + </dependency> + </dependencies> + <configuration> + <sourceDocumentName>Getting_Started.xml</sourceDocumentName> + <imageResource> + <directory>${basedir}/src/main/docbook/en-US/images</directory> + <includes> + <include>*.png</include> + </includes> + </imageResource> + <!-- cssResource> + <directory>${basedir}/src/main/docbook/css</directory> + </cssResource--> + <targetDirectory>${basedir}/target/docbook/en-US</targetDirectory> + <formats> + <format> + <formatName>html</formatName> + <stylesheetResource>classpath:/xslt/org/jboss/xhtml.xsl</stylesheetResource> + <finalName>index.html</finalName> + </format> + <!-- + <format> + <formatName>html_single</formatName> + <stylesheetResource>classpath:/xslt/org/jboss/xhtml-single.xsl</stylesheetResource> + <finalName>index.html</finalName> + </format> + --> + <format> + <formatName>pdf</formatName> + <stylesheetResource>classpath:/xslt/org/jboss/pdf.xsl</stylesheetResource> + <finalName>userguide_en.pdf</finalName> + </format> + </formats> + <options> + <xincludeSupported>true</xincludeSupported> + <xmlTransformerType>saxon</xmlTransformerType> + <!-- needed for uri-resolvers; can be ommitted if using 'current' uri scheme --> + <!-- could also locate the docbook dependency and inspect its version... --> + <docbookVersion>1.72.0</docbookVersion> + </options> + </configuration> + </plugin> + </plugins> + </build> </project> \ No newline at end of file Added: trunk/docs/gettingstarted/src/main/docbook/en-US/Getting_Started.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/Getting_Started.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/Getting_Started.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,59 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ +<!ENTITY versionNumber "0.3"> +<!ENTITY copyrightYear "2008"> +<!ENTITY copyrightHolder "Red Hat Middleware, LLC."> +]> +<book lang="en"> + <bookinfo> + <title>JBoss DNA</title> + <subtitle>Getting Started Guide</subtitle> + <releaseinfo>&versionNumber;</releaseinfo> + <productnumber>&versionNumber;</productnumber> + <issuenum>1</issuenum> + <mediaobject> + <imageobject role="fo"> + <imagedata fileref="dna-logo.png" align="center"/> + </imageobject> + <imageobject role="html"> + <imagedata fileref="dna-logo.png" depth="3cm"/> + </imageobject> + </mediaobject> + <copyright> + <year>&copyrightYear;</year> + <holder>&copyrightHolder;</holder> + </copyright> + <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/author_group.xml"/> + <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/legal_notice.xml"/> + </bookinfo> + <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/preface.xml"/> + <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/introduction.xml"/> + <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/understanding_dna.xml"/> + <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/downloading_and_running.xml"/> + <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/using_dna.xml"/> + <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/custom_sequencers.xml"/> + <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/future.xml"/> +</book> Added: trunk/docs/gettingstarted/src/main/docbook/en-US/content/author_group.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/content/author_group.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/content/author_group.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,31 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE authorgroup PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> +<authorgroup> + <corpauthor>Randall M. Hauch</corpauthor> + <corpauthor>John Verhaeg</corpauthor> + <corpauthor>Stefano Maestri</corpauthor> + <corpauthor>Serge Emmanuel Pagop</corpauthor> +</authorgroup> \ No newline at end of file Added: trunk/docs/gettingstarted/src/main/docbook/en-US/content/custom_sequencers.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/content/custom_sequencers.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/content/custom_sequencers.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,403 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> +<chapter id="custom_sequencers"> + <title>Creating custom sequencers</title> + <para>The current release of JBoss DNA comes with two sequencers: one that extracts metadata from a variety of image file formats, + and another that extracts some of the ID3 metadata from MP3 audio files. However, it's very easy to create your own + sequencers and to then configure JBoss DNA to use them in your own application. + </para> + <para> + Creating a custom sequencer involves the following steps: + <itemizedlist> + <listitem> + <para>Create a Maven 2 project for your sequencer;</para> + </listitem> + <listitem> + <para>Implement the <code>org.jboss.dna.spi.sequencers.StreamSequencer</code> interface with your own implementation, and create unit tests to verify + the functionality and expected behavior;</para> + </listitem> + <listitem> + <para>Add the sequencer configuration to the JBoss DNA <code>SequencingService</code> in your application + as described in the <link linkend="using_dna">previous chapter</link>; and</para> + </listitem> + <listitem> + <para>Deploy the JAR file with your implementation (as well as any dependencies), and make them available to JBoss DNA + in your application.</para> + </listitem> + </itemizedlist> + It's that simple. + </para> + <sect1 id="custom_sequencer_project"> + <title>Creating the Maven 2 project</title> + <para>The first step is to create the Maven 2 project that you can use to compile your code and build the JARs. + Maven 2 automates a lot of the work, and since you're already <link linkend="downloading_and_running">set up to use Maven</link>, + using Maven for your project will save you a lot of time and effort. Of course, you don't have to use Maven 2, but then you'll + have to get the required libraries and manage the compiling and building process yourself.</para> + <note> + <para>JBoss DNA may provide in the future a Maven archetype for creating sequencer projects. If you'd find this useful + and would like to help create it, please <link linkend="preface">join the community</link>.</para> + </note> + <note> + <para>The <code>dna-sequencer-images</code> project is a small, self-contained sequencer implementation that + has only the minimal dependencies. Starting with this project's source and modifying it to suit your needs may be the easiest way to get started. + See the subversion repository: <ulink url="http://anonsvn.jboss.org/repos/dna/trunk/extensions/dna-sequenc... + </para> + </note> + <para>You can create your Maven project any way you'd like. For examples, see the <ulink url="http://maven.apache.org/guides/getting-started/index.html#How_d... 2 documentation</ulink>. + Once you've done that, just add the dependencies in your project's <code>pom.xml</code> dependencies section:</para> + <programlisting role="XML"><![CDATA[ +<dependency> + <groupId>org.jboss.dna</groupId> + <artifactId>dna-common</artifactId> + <version>0.1</version> +</dependency> +<dependency> + <groupId>org.jboss.dna</groupId> + <artifactId>dna-spi</artifactId> + <version>0.1</version> +</dependency> +<dependency> + <groupId>org.slf4j</groupId> + <artifactId>slf4j-api</artifactId> +</dependency> + ]]></programlisting> + <para>These are minimum dependencies required for compiling a sequencer. Of course, you'll have to add + other dependencies that your sequencer needs.</para> + <para>As for testing, you probably will want to add more dependencies, such as those listed here:</para> + <programlisting role="XML"><![CDATA[ +<dependency> + <groupId>junit</groupId> + <artifactId>junit</artifactId> + <version>4.4</version> + <scope>test</scope> +</dependency> +<dependency> + <groupId>org.hamcrest</groupId> + <artifactId>hamcrest-library</artifactId> + <version>1.1</version> + <scope>test</scope> +</dependency> +<!-- Logging with Log4J --> +<dependency> + <groupId>org.slf4j</groupId> + <artifactId>slf4j-log4j12</artifactId> + <version>1.4.3</version> + <scope>test</scope> +</dependency> +<dependency> + <groupId>log4j</groupId> + <artifactId>log4j</artifactId> + <version>1.2.14</version> + <scope>test</scope> +</dependency> + ]]></programlisting> + <para>Testing JBoss DNA sequencers does not require a JCR repository or the JBoss DNA services. (For more detail, + see the <link linkend="testing_custom_sequencers">testing section</link>.) However, if you want to do + integration testing with a JCR repository and the JBoss DNA services, you'll need additional dependencies for these libraries.</para> + <programlisting role="XML"><![CDATA[ +<dependency> + <groupId>org.jboss.dna</groupId> + <artifactId>dna-repository</artifactId> + <version>0.1</version> + <scope>test</scope> +</dependency> +<!-- Java Content Repository API --> +<dependency> + <groupId>javax.jcr</groupId> + <artifactId>jcr</artifactId> + <version>1.0.1</version> + <scope>test</scope> +</dependency> +<!-- Apache Jackrabbit (JCR Implementation) --> +<dependency> + <groupId>org.apache.jackrabbit</groupId> + <artifactId>jackrabbit-api</artifactId> + <version>1.3.3</version> + <scope>test</scope> + <!-- Exclude these since they are included in JDK 1.5 --> + <exclusions> + <exclusion> + <groupId>xml-apis</groupId> + <artifactId>xml-apis</artifactId> + </exclusion> + <exclusion> + <groupId>xerces</groupId> + <artifactId>xercesImpl</artifactId> + </exclusion> + </exclusions> +</dependency> +<dependency> + <groupId>org.apache.jackrabbit</groupId> + <artifactId>jackrabbit-core</artifactId> + <version>1.3.3</version> + <scope>test</scope> + <!-- Exclude these since they are included in JDK 1.5 --> + <exclusions> + <exclusion> + <groupId>xml-apis</groupId> + <artifactId>xml-apis</artifactId> + </exclusion> + <exclusion> + <groupId>xerces</groupId> + <artifactId>xercesImpl</artifactId> + </exclusion> + </exclusions> +</dependency> + ]]></programlisting> + <para>At this point, your project should be set up correctly, and you're ready to move on to + <link linkend="custom_sequencer_implementation">writing the Java implementation</link> for your sequencer.</para> + </sect1> + <sect1 id="custom_sequencer_implementation"> + <title>Implementing the StreamSequencer interface</title> + <para>After creating the project and setting up the dependencies, the next step is to create a Java class that implements + the <code>org.jboss.dna.spi.sequencers.StreamSequencer</code> interface. This interface is very straightforward + and involves a single method:</para> + <programlisting role="JAVA"><![CDATA[ +public interface StreamSequencer { + + /** + * Sequence the data found in the supplied stream, placing the output + * information into the supplied map. + * + * @param stream the stream with the data to be sequenced; never null + * @param output the output from the sequencing operation; never null + * @param progressMonitor the progress monitor that should be kept + * updated with the sequencer's progress and that should be + * frequently consulted as to whether this operation has been cancelled. + */ + void sequence( InputStream stream, SequencerOutput output, ProgressMonitor progressMonitor ); + ]]></programlisting> + <para>The job of a stream sequencer is to process the data in the supplied stream, and place into the <code>SequencerOutput</code> + any information that is to go into the JCR repository. JBoss DNA figures out when your sequencer should be called + (of course, using the sequencing configuration you'll add in a bit), and then makes sure the generated information + is saved in the correct place in the repository. + </para> + <para>The <code>SequencerOutput</code> class is fairly easy to use. There are basically two methods you need to call. + One method sets the property values, while the other sets references to other nodes in the repository. Use these + methods to describe the properties of the nodes you want to create, using relative paths for the nodes and + valid JCR property names for properties and references. JBoss DNA will ensure that nodes are created or updated + whenever they're needed.</para> + <programlisting role="JAVA"><![CDATA[ +public interface SequencerOutput { + + /** + * Set the supplied property on the supplied node. The allowable + * values are any of the following: + * - primitives (which will be autoboxed) + * - String instances + * - String arrays + * - byte arrays + * - InputStream instances + * - Calendar instances + * + * @param nodePath the path to the node containing the property; + * may not be null + * @param property the name of the property to be set + * @param values the value(s) for the property; may be empty if + * any existing property is to be removed + */ + void setProperty( String nodePath, String property, Object... values ); + + /** + * Set the supplied reference on the supplied node. + * + * @param nodePath the path to the node containing the property; + * may not be null + * @param property the name of the property to be set + * @param paths the paths to the referenced property, which may be + * absolute paths or relative to the sequencer output node; + * may be empty if any existing property is to be removed + */ + void setReference( String nodePath, String property, String... paths ); +} + ]]></programlisting> + <para>JBoss DNA will create nodes of type <code>nt:unstructured</code> unless you specify the value for the + <code>jcr:primaryType</code> property. You can also specify the values for the <code>jcr:mixinTypes</code> property + if you want to add mixins to any node.</para> + <para>For a complete example of a sequencer, let's look at the <code>org.jboss.dna.sequencers.image.ImageMetadataSequencer</code> + implementation:</para> + <programlisting role="JAVA"><![CDATA[ +public class ImageMetadataSequencer implements StreamSequencer { + + public static final String METADATA_NODE = "image:metadata"; + public static final String IMAGE_PRIMARY_TYPE = "jcr:primaryType"; + public static final String IMAGE_MIXINS = "jcr:mixinTypes"; + public static final String IMAGE_MIME_TYPE = "jcr:mimeType"; + public static final String IMAGE_ENCODING = "jcr:encoding"; + public static final String IMAGE_FORMAT_NAME = "image:formatName"; + public static final String IMAGE_WIDTH = "image:width"; + public static final String IMAGE_HEIGHT = "image:height"; + public static final String IMAGE_BITS_PER_PIXEL = "image:bitsPerPixel"; + public static final String IMAGE_PROGRESSIVE = "image:progressive"; + public static final String IMAGE_NUMBER_OF_IMAGES = "image:numberOfImages"; + public static final String IMAGE_PHYSICAL_WIDTH_DPI = "image:physicalWidthDpi"; + public static final String IMAGE_PHYSICAL_HEIGHT_DPI = "image:physicalHeightDpi"; + public static final String IMAGE_PHYSICAL_WIDTH_INCHES = "image:physicalWidthInches"; + public static final String IMAGE_PHYSICAL_HEIGHT_INCHES = "image:physicalHeightInches"; + + /** + * {@inheritDoc} + */ + public void sequence( InputStream stream, SequencerOutput output, + ProgressMonitor progressMonitor ) { + progressMonitor.beginTask(10, ImageSequencerI18n.sequencerTaskName); + + ImageMetadata metadata = new ImageMetadata(); + metadata.setInput(stream); + metadata.setDetermineImageNumber(true); + metadata.setCollectComments(true); + + // Process the image stream and extract the metadata ... + if (!metadata.check()) { + metadata = null; + } + progressMonitor.worked(5); + if (progressMonitor.isCancelled()) return; + + // Generate the output graph if we found useful metadata ... + if (metadata != null) { + // Place the image metadata into the output map ... + output.setProperty(METADATA_NODE, IMAGE_PRIMARY_TYPE, "image:metadata"); + // output.psetProperty(METADATA_NODE, IMAGE_MIXINS, ""); + output.setProperty(METADATA_NODE, IMAGE_MIME_TYPE, metadata.getMimeType()); + // output.setProperty(METADATA_NODE, IMAGE_ENCODING, ""); + output.setProperty(METADATA_NODE, IMAGE_FORMAT_NAME, metadata.getFormatName()); + output.setProperty(METADATA_NODE, IMAGE_WIDTH, metadata.getWidth()); + output.setProperty(METADATA_NODE, IMAGE_HEIGHT, metadata.getHeight()); + output.setProperty(METADATA_NODE, IMAGE_BITS_PER_PIXEL, metadata.getBitsPerPixel()); + output.setProperty(METADATA_NODE, IMAGE_PROGRESSIVE, metadata.isProgressive()); + output.setProperty(METADATA_NODE, IMAGE_NUMBER_OF_IMAGES, metadata.getNumberOfImages()); + output.setProperty(METADATA_NODE, IMAGE_PHYSICAL_WIDTH_DPI, metadata.getPhysicalWidthDpi()); + output.setProperty(METADATA_NODE, IMAGE_PHYSICAL_HEIGHT_DPI, metadata.getPhysicalHeightDpi()); + output.setProperty(METADATA_NODE, IMAGE_PHYSICAL_WIDTH_INCHES, metadata.getPhysicalWidthInch()); + output.setProperty(METADATA_NODE, IMAGE_PHYSICAL_HEIGHT_INCHES, metadata.getPhysicalHeightInch()); + } + + progressMonitor.done(); + } +} + ]]></programlisting> + <para> + Notice how the image metadata is extracted and the output graph is generated. A single node is created with the name <code>image:metadata</code> + and with the <code>image:metadata</code> node type. No mixins are defined for the node, but several properties are set on the node + using the values obtained from the image metadata. After this method returns, the constructed graph will be saved to the repository + in all of the places defined by its configuration. (This is why only relative paths are used in the sequencer.) + </para> + <para>Also note how the progress monitor is used. Reporting progress through the supplied <code>ProgressMonitor</code> is very easy, and it ensures that JBoss DNA + can accurately monitor and report the status of sequencing activities to the users. At the beginning of the operation, call + <code>beginTask(...)</code> with a meaningful message describing + the operation and a total for the amount of work that will be done by this sequencer. Then perform the sequencing work, + periodically reporting work by specifying the incremental amount of work with the <code>worked(double)</code> method, or + by creating a subtask with the <code>createSubtask(double)</code> method and reporting work against that subtask + monitor. + </para> + <para>Your method should periodically use the ProgressMonitor's <code>isCancelled()</code> method to check whether the operation has been + cancelled.. If this method returns true, the implementation should abort all work as + soon as possible and close any resources that were acquired or opened. + </para> + <para> + Finally, when your sequencing operation is completed, it should call <code>done()</code> on the progress monitor. + </para> + </sect1> + <sect1 id="testing_custom_sequencers"> + <title>Testing custom sequencers</title> + <para>The sequencing framework was designed to make testing sequencers much easier. In particular, the + <code>StreamSequencer</code> interface does not make use of the JCR API. So instead of requiring a fully-configured + JCR repository and JBoss DNA system, unit tests for a sequencer can focus on testing that the content is + processed correctly and the desired output graph is generated.</para> + <note> + <para>For a complete example of a sequencer unit test, see the <code>ImageMetadataSequencerTest</code> unit test + in the <code>org.jboss.dna.sequencer.images</code> package of the <code>dna-sequencers-image</code> project. + </para> + </note> + <para>The following code fragment shows one way of testing a sequencer, using JUnit 4.4 assertions and + some of the classes made available by JBoss DNA. Of course, + this example code does not do any error handling and does not make all the assertions a real test would.</para> + <programlisting role="JAVA"><![CDATA[ +Sequencer sequencer = new ImageMetadataSequencer(); +MockSequencerOutput output = new MockSequencerOutput(); +ProgressMonitor progress = new SimpleProgressMonitor("Test activity"); +InputStream stream = null; +try { + stream = this.getClass().getClassLoader().getResource("caution.gif").openStream(); + sequencer.sequence(stream,output,progress); // writes to 'output' + assertThat(output.getPropertyValues("image:metadata", "jcr:primaryType"), + is(new Object[] {"image:metadata"})); + assertThat(output.getPropertyValues("image:metadata", "jcr:mimeType"), + is(new Object[] {"image/gif"})); + // ... make more assertions here + assertThat(output.hasReferences(), is(false)); +} finally { + stream.close(); +} + ]]></programlisting> + <para>It's also useful to test that a sequencer produces no output for something it should not understand:</para> + <programlisting role="JAVA"><![CDATA[ +Sequencer sequencer = new ImageMetadataSequencer(); +MockSequencerOutput output = new MockSequencerOutput(); +ProgressMonitor progress = new SimpleProgressMonitor("Test activity"); +InputStream stream = null; +try { + stream = this.getClass().getClassLoader().getResource("caution.pict").openStream(); + sequencer.sequence(stream,output,progress); // writes to 'output' + assertThat(output.hasProperties(), is(false)); + assertThat(output.hasReferences(), is(false)); +} finally { + stream.close(); +} + ]]></programlisting> + <para>These are just two simple tests that show ways of testing a sequencer. Some tests may get quite involved, + especially if a lot of output data is produced. + </para> + <para>It may also be useful to create some integration tests + that <link linkend="using_dna">configure JBoss DNA</link> to use a custom sequencer, and to then upload + content using the JCR API, verifying that the custom sequencer did run. However, remember that JBoss DNA + runs sequencers asynchronously in the background, and you must sychronize your tests to ensure that the + sequencers have a chance to run before checking the results. (One way of doing this (although, granted, not always reliable) is to wait for a second + after uploading your content, shutdown the <code>SequencingService</code> and await its termination, + and then check that the sequencer output has been saved to the JCR repository. For an example of this technique, + see the <code>SequencingClientTest</code> unit test in the example application.) + </para> + </sect1> + <sect1 id="deploying_custom_sequencers"> + <title>Deploying custom sequencers</title> + <para>The first step of deploying a sequencer consists of adding/changing the sequencer configuration (e.g., <code>SequencerConfig</code>) + in the <code>SequencingService</code>. This was covered in the <link linkend="sequencing_service">previous chapter</link>. + </para> + <para> + The second step is to make the sequencer implementation available to JBoss DNA. At this time, the JAR containing + your new sequencer, as well as any JARs that your sequencer depends on, should be placed on your application classpath.</para> + <note> + <para>A future goal of JBoss DNA is to allow sequencers, connectors, and other extensions to be easily deployed into + a runtime repository. This process will not only be much simpler, but it will also provide JBoss DNA + with the information necessary to update configurations and create the appropriate class loaders for each extension. + Having separate class loaders for each extension helps prevent the pollution of the common classpath, + facilitates an isolated runtime environment to eliminate any dependency conflicts, and may potentially + enable hot redeployment of newer extension versions. + </para> + </note> + </sect1> +</chapter> Added: trunk/docs/gettingstarted/src/main/docbook/en-US/content/downloading_and_running.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/content/downloading_and_running.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/content/downloading_and_running.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,282 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> +<chapter id="downloading_and_running"> + <title>Running the example application</title> + <para> + This chapter provides instructions for downloading and running a sample application that demonstrates how JBoss DNA works + with a JCR repository to automatically sequence changing content to extract useful information. So read on to get the simple + application running, and then in the <link linkend="using_dna">next chapter</link> + we'll dive into the source code for the example and show how to use JBoss DNA in your own applications. </para> + <para>JBoss DNA uses Maven 2 for its build system, as is this example. Using Maven 2 has several advantages, including + the ability to manage dependencies. If a library is needed, Maven automatically finds and downloads that library, plus + everything that library needs. This means that it's very easy to build the examples - or even create a maven project that + depends on the JBoss DNA JARs.</para> + <note> + <para> + To use Maven with JBoss DNA, you'll need to have <ulink url="http://java.sun.com/javase/downloads/index_jdk5.jsp">JDK 5 or 6</ulink> + and Maven 2.0.7 (or higher).</para> + <para> + Maven can be downloaded from <ulink url="http://maven.apache.org/">http://maven.apache.org/</...;, and is installed by unzipping the + <code>maven-2.0.7-bin.zip</code> file to a convenient location on your local disk. Simply add <code>$MAVEN_HOME/bin</code> + to your path and add the following profile to your <code>~/.m2/settings.xml</code> file:</para> + <programlisting role="XML"><![CDATA[ +<settings> + <profiles> + <profile> + <id>jboss.repository</id> + <activation> + <property> + <name>!jboss.repository.off</name> + </property> + </activation> + <repositories> + <repository> + <id>snapshots.jboss.org</id> + <url>http://snapshots.jboss.org/maven2</url> + <snapshots> + <enabled>true</enabled> + </snapshots> + </repository> + <repository> + <id>repository.jboss.org</id> + <url>http://repository.jboss.org/maven2</url> + <snapshots> + <enabled>false</enabled> + </snapshots> + </repository> + </repositories> + <pluginRepositories> + <pluginRepository> + <id>repository.jboss.org</id> + <url>http://repository.jboss.org/maven2</url> + <snapshots> + <enabled>false</enabled> + </snapshots> + </pluginRepository> + <pluginRepository> + <id>snapshots.jboss.org</id> + <url>http://snapshots.jboss.org/maven2</url> + <snapshots> + <enabled>true</enabled> + </snapshots> + </pluginRepository> + </pluginRepositories> + </profile> + </profiles> +</settings> +]]></programlisting> + <para>This profile informs Maven of the two JBoss repositories (snapshots and releases) that contain + all of the JARs for JBoss DNA and all dependent libraries.</para> + </note> + <sect1 id="downloading"> + <title>Downloading and compiling</title> + <para>The next step is to <ulink url="http://www.jboss.org/file-access/default/members/dna/downloads/... + the example for this Getting Started guide, and extract the contents to a convenient location on your local disk. + You'll find the example contains the following files, which are organized according to the standard Maven directory structure:</para> + <programlisting><![CDATA[ +examples/pom.xml + sequencers/pom.xml + /src/main/assembly + /config + /java + /resources + /test/java + /resources +]]></programlisting> + <para>There are essentially two Maven projects: a <code>sequencers</code> project and a parent project. All of the source + for the example is located in the <code>sequencers</code> subdirectory. And you may have noticed that none + of the JBoss DNA libraries are there. This is where Maven comes in. The two <code>pom.xml</code> files tell + Maven everything it needs to know about what libraries are required and how to build the example.</para> + <para>In a terminal, go to the <code>examples</code> directory and run <emphasis role="strong"><code>mvn install</code></emphasis>. + This command downloads all of the JARs necessary to compile and build the example, including the JBoss DNA libraries, + the libraries they depend on, and any missing Maven components. (These are downloaded from the JBoss repositories + only once and saved on your machine. This means that the next time you run Maven, all the libraries will + already be available locally, and the build will run much faster.) The command then continues by compiling the example's source + code (and unit tests) and running the unit tests. The build is successful if you see the following:</para> + <programlisting><![CDATA[ +$ mvn install +... +[INFO] ------------------------------------------------------------------------ +[INFO] Reactor Summary: +[INFO] ------------------------------------------------------------------------ +[INFO] Getting Started examples .............................. SUCCESS [2.106s] +[INFO] Sequencer Examples .................................... SUCCESS [9.768s] +[INFO] ------------------------------------------------------------------------ +[INFO] ------------------------------------------------------------------------ +[INFO] BUILD SUCCESSFUL +[INFO] ------------------------------------------------------------------------ +[INFO] Total time: 12 seconds +[INFO] Finished at: Wed May 07 12:00:06 CDT 2008 +[INFO] Final Memory: 14M/28M +[INFO] ------------------------------------------------------------------------ +$ ]]></programlisting> + <para>If there are errors, check whether you have the correct version of Maven installed and that you've correctly updated + your Maven settings as described above.</para> + <para>If you've successfully built the examples, there will be a new <code>examples/sequencers/target/</code> directory that contains + all of the generated output, including a <code>dna-example-sequencers-basic.dir/</code> subdirectory that contains the following: + <itemizedlist> + <listitem> + <para><emphasis role="strong"><code>run.sh</code></emphasis> is the *nix shell script that will run the example.</para> + </listitem> + <listitem> + <para><emphasis role="strong"><code>log4j.properties</code></emphasis> + is the Log4J configuration file. + </para> + </listitem> + <listitem> + <para><emphasis role="strong"><code>jackrabbitConfig.xml</code></emphasis> + is the Jackrabbit configuration file, which is set up to use a transient in-memory repository. + </para> + </listitem> + <listitem> + <para><emphasis role="strong"><code>jackrabbitNodeTypes.cnd</code></emphasis> + defines the additional JCR node types used by this example. + </para> + </listitem> + <listitem> + <para><emphasis role="strong"><code>sample1.mp3</code></emphasis> + is a sample MP3 audio file you'll use later to upload into the repository. + </para> + </listitem> + <listitem> + <para><emphasis role="strong"><code>caution.gif</code></emphasis>, <emphasis role="strong"><code>caution.png</code></emphasis>, and <emphasis role="strong"><code>caution.jpg</code></emphasis> + are images that you'll use later and upload into the repository. + </para> + </listitem> + <listitem> + <para><emphasis role="strong"><code>lib</code></emphasis> + subdirectory contains the JARs for all of the JBoss DNA artifacts as well as those for other libraries required + by JBoss DNA and the example. + </para> + </listitem> + </itemizedlist> + </para> + <note> + <para>JBoss DNA 0.1 and the examples are currently tested with <ulink url="http://jackrabbit.apache.org/">Apache Jackrabbit</ulink> version 1.3.3. + This version is stable and used by a number of other projects and applications. However, you should be able to use a newer + version of Jackrabbit, as long as that version uses the same JCR API. For example, version 1.4.2 was released on March 26, 2008 and + should be compatible.</para> + <para>Just remember, if the version of Jackrabbit you want to use for these examples is not in the Maven repository, + you'll have to either add it or add it locally. For more information, see the <ulink url="http://maven.apache.org/">Maven documentation</ulink>. + </para> + </note> + </sect1> + <sect1 id="running"> + <title>Running the example</title> + <para>This example consists of a client application that sets up an in-memory JCR repository and that allows a user to + upload files into that repository. The client also sets up the DNA services with two sequencers so that if any of the + uploaded files are PNG, JPEG, GIF, BMP or other images, DNA will automatically extract the image's metadata (e.g., image + format, physical size, pixel density, etc.) and store that in the repository. Alternatively, if the uploaded file + is an MP3 audio file, DNA will extract some of the ID3 metadata (e.g., the author, title, album, year and comment) + and store that in the repository.</para> + <para> + To run the client application, go to the <code>examples/sequencers/target/dna-example-sequencers-basic.dir/</code> + directory and type <code>./run.sh</code>. You should see the command-line client and its menus in your terminal: + <figure id="xample-sequencer-cli-client"> + <title>Example Client</title> + <graphic align="center" scale="100" fileref="example-sequencer-cli-client.png"/> + </figure> + From this menu, you can upload a file into the repository, search for media in the repository, print sequencing statistics, + or quit the application.</para> + <para> + The first step is to upload one of the example images. If you type 'u' and press return, you'll be prompted to supply the + path to the file you want to upload. Since the application is running from within the + <code>examples/sequencers/target/dna-example-sequencers-basic.dir/</code> directory, you can specify any of the files + in that directory without specifying the path: + <figure id="example-sequencer-upload"> + <title>Uploading an image using the Example Client</title> + <graphic align="center" scale="100" fileref="example-sequencer-upload.png"/> + </figure> + You can specify any fully-qualified or relative path. The application will notify you if it cannot find the file you + specified. The example client configures JBoss DNA to sequence and MP3 audio files and image files with one of + the following extensions (technically, nodes that have names ending in the following): + <code>jpg</code>, <code>jpeg</code>, <code>gif</code>, <code>bmp</code>, <code>pcx</code>, <code>png</code>, + <code>iff</code>, <code>ras</code>, <code>pbm</code>, <code>pgm</code>, <code>ppm</code>, and <code>psd</code>. + Files with other extensions in the repository path will be ignored. For your convenience, the example provides several + files that will be sequenced (<code>caution.png</code>, <code>caution.jpg</code>, <code>caution.gif</code>, and + <code>sample1.mp3</code>) and one image that will not be sequenced (<code>caution.pict</code>). Feel free to try other files. + </para> + <para> + After you have specified the file you want to upload, the example application asks you where in the repository you'd like to + place the file. (If you want to use the suggested location, just press <code>return</code>.) The client application + uses the JCR API to upload the file to that location in the repository, creating any nodes (of type <code>nt:folder</code>) + for any directories that don't exist, and creating a node (of type <code>nt:file</code>) for the file. And, per the JCR specification, + the application creates a <code>jcr:content</code> node (of type <code>nt:resource</code>) under the file node. + The file contents are placed on this <code>jcr:content</code> node in the <code>jcr:data</code> property. For example, if you specify + <code>/a/b/caution.png</code>, the following structure will be created in the repository:</para> + <programlisting><![CDATA[ +/a (nt:folder) + /b (nt:folder) + /caution.png (nt:file) + /jcr:content (nt:resource) + @jcr:data = {contents of the file} + @jcr:mimeType = {mime type of the file} + @jcr:lastModified = {now} +]]></programlisting> + <para>Other kinds of files are treated in a similar way.</para> + <para>When the client uploads the file using the JCR API, DNA gets notified of the changes, consults the sequencers to see whether + any of them are interested in the new or updated content, and if so runs those sequencers. The image sequencer processes image + files for metadata, and any metadata found is stored under the <code>/images</code> branch of the repository. The MP3 sequencer + processes MP3 audio files for metadata, and any metadata found is stored under the <code>/mp3s</code> + branch of the repository. All of this happens asynchronously, so any DNA activity doesn't impede or slow down the client + activities.</para> + <para>So, after the file is uploaded, you can search the repository for the image metadata using the "s" menu option: + <figure id="example-sequencer-search"> + <title>Searching for media using the Example Client</title> + <graphic align="center" scale="100" fileref="example-sequencer-search.png"/> + </figure> + Here are the search results after the <code>sample1.mp3</code> audio file has been uploaded (to the <code>/a/b/sample1.mp3</code> location): + <figure id="example-sequencer-search-with-mp3"> + <title>Searching for media using the Example Client</title> + <graphic align="center" scale="100" fileref="example-sequencer-search-with-mp3.png"/> + </figure> + You can also display the sequencing statistics using the "d" menu option: + <figure id="example-sequencer-statistics"> + <title>Sequencing statistics using the Example Client</title> + <graphic align="center" scale="100" fileref="example-sequencer-statistics.png"/> + </figure> + These stats show how many nodes were sequenced, and how many nodes were skipped because they didn't apply to the sequencer's + criteria. + </para> + <note> + <para>There will probably be more nodes skipped than sequenced, since there are more <code>nt:folder</code> and <code>nt:resource</code> + nodes than there are <code>nt:file</code> nodes with acceptable names.</para> + </note> + <para>You can repeat this process with other files. Any file that isn't an image or MP3 files (as recognized by the sequencing configurations + that we'll describe later) will not be sequenced.</para> + </sect1> + <sect1 id="downloading_and_running_review"> + <title>Summarizing what we just did</title> + <para>In this chapter you downloaded and installed the example application and used it to upload files into a + JCR repository. JBoss DNA automatically sequenced the image and/or MP3 files you uploaded, extracted the metadata from the + files, and stored that metadata inside the repository. The application allowed you to see this metadata + and the sequencing statistics.</para> + <para>This application was very simplistic. In fact, running through the example probably only took you a minute or two. + So while this application won't win any awards, it does show the basics of what JBoss DNA can do.</para> + <para>In the <link linkend="using_dna">next chapter</link> we'll venture into the code to get an understanding + of how JBoss DNA actually works and how you can use it in your own applications.</para> + </sect1> +</chapter> Added: trunk/docs/gettingstarted/src/main/docbook/en-US/content/future.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/content/future.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/content/future.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,43 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> +<chapter id="future"> + <title>Looking to the future</title> + <para>What's next for JBoss DNA? Well, the sequencing system is just the beginning. With this release, the sequencing system + is stable enough so that more <link linkend="sequencers">sequencers</link> can be developed and used within your own applications. + If you're interested in getting involved with the JBoss DNA project, consider picking up one of the sequencers on our + <ulink url="http://jira.jboss.org/jira/browse/DNA?report=com.atlassian.jira...;. + Or, check out <ulink url="http://jira.jboss.org/jira/secure/IssueNavigator.jspa?reset=tru... + for the list of sequencers we've thought of. If you think of one that's not there, please add it to JIRA! </para> + <para>The next release will focus on creating the <link linkend="federation">federation engine</link> and connectors + for several popular and ubiquitous systems. The 0.2 release will likely only federate information in a read-only manner, + but updates will soon follow. Also, during the early part of the next release, the JBoss DNA project will switch to use JDK 6. + Java 5 is being end-of-lifed, so we want to move to a supported JDK. However, a number of JBoss projects and products continue to + require Java 5, so our next release will most likely use JDK 6 with Java 5 compatibility.</para> + <para>Other components on our roadmap include a web user interface, a REST-ful server, and a view system that allows domain-specific + views of information in the repository. These components are farther out on our roadmap, and at this time have not been + targeted to a particular release. If any of these are of interest to you, please <link linkend="preface">get involved</link> + in the community.</para> +</chapter> Added: trunk/docs/gettingstarted/src/main/docbook/en-US/content/introduction.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/content/introduction.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/content/introduction.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,119 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> +<chapter id="introduction"> + <title>Introduction</title> + <para>There are a lot of choices for how applications can store information persistently so that it can be accessed at a + later time and by other processes. The challenge developers face is how to use an approach that most closely matches the + needs of their application. This choice becomes more important as developers choose to focus their efforts on + application-specific logic, delegating much of the responsibilities for persistence to libraries and frameworks.</para> + <para> + Perhaps one of the easiest techniques is to simply store information in + <emphasis>files</emphasis> + . The Java language makes working with files relatively easy, but Java really doesn't provide many bells and whistles. So + using files is an easy choice when the information is either not complicated (for example property files), or when users may + need to read or change the information outside of the application (for example log files or configuration files). But using + files to persist information becomes more difficult as the information becomes more complex, as the volume of it increases, + or if it needs to be accessed by multiple processes. For these situations, other techniques often offer better choices. + </para> + <para> + Another technique built into the Java language is + <emphasis>Java serialization</emphasis> + , which is capable of persisting the state of an object graph so that it can be read back in at a later time. However, Java + serialization can quickly become tricky if the classes are changed, and so it's beneficial usually when the information is + persisted for a very short period of time. For example, serialization is sometimes used to send an object graph from one + process to another. + </para> + <para> + One of the more popular persistence technologies is the + <emphasis>relational database</emphasis> + . Relational database management systems have been around for decades and are very capable. The Java Database Connectivity + (JDBC) API provides a standard interface for connecting to and interacting with relational databases. However, it is a + low-level API that requires a lot of code to use correctly, and it still doesn't abstract away the DBMS-specific SQL + grammar. Also, working with relational data in an object-oriented language can feel somewhat unnatural, so many developers + map this data to classes that fit much more cleanly into their application. The problem is that manually creating this + mapping layer requires a lot of repetitive and non-trivial JDBC code. + </para> + <para> + <emphasis>Object-relational mapping</emphasis> + libraries automate the creation of this mapping layer and result in far less code that is much more maintainable with + performance that is often as good as (if not better than) handwritten JDBC code. The new + <ulink url="http://java.sun.com/developer/technicalArticles/J2EE/jpa/"... Persistence API (JPA)</ulink> + provide a standard mechanism for defining the mappings (through annotations) and working with these entity objects. Several + commercial and open-source libraries implement JPA, and some even offer additional capabilities and features that go beyond + JPA. For example, + <ulink url="http://www.hibernate.org">Hibernate</ulink> + is one of the most feature-rich JPA implementations and offers object caching, statement caching, extra association + mappings, and other features that help to improve performance and usefulness. + </para> + <para> + While relational databases and JPA are solutions that work for many applications, they become more limited in cases when the + information structure is highly flexible, is not known + <emphasis>a priori</emphasis> + , or is subject to frequent change and customization. In these situations, + <emphasis>content repositories</emphasis> + may offer a better choice for persistence. Content repositories are almost a hybrid between relational databases and file + systems, and typically provide other capabilities as well, including versioning, indexing, search, access control, + transactions, and observation. Because of this, content repositories are used by content management systems (CMS), document + management systems (DMS), and other applications that manage electronic files (e.g., documents, images, multi-media, web + content, etc.) and metadata associated with them (e.g., author, date, status, security information, etc.). The + <ulink url="http://www.jcp.org/en/jsr/detail?id=170">Content Repository for Java technology API</ulink> + provides a standard Java API for working with content repositories. Abbreviated "JCR", this API was developed as part of the + Java Community Process under + <ulink url="http://www.jcp.org/en/jsr/detail?id=170">JSR-170</ul... + and is being revised under + <ulink url="http://www.jcp.org/en/jsr/detail?id=283">JSR-283</ul... + . + </para> + <para> + The + <emphasis>JBoss DNA project</emphasis> + is building the tools and services that surround content repositories. Nearly all of these capabilities are to be hidden + below the JCR API and involve automated processing of the information in the repository. Thus, JBoss DNA can add value to + existing repository implementations. For example, JCR repositories offer the ability to upload files into the repository and + have the file content indexed for search purposes. JBoss DNA also defines a library for "sequencing" content - to extract + meaningful information from that content and store it in the repository, where it can then be searched, accessed, and + analyzed using the JCR API. + </para> + <para> JBoss DNA is building other features as well. One goal of JBoss DNA is to create federated repositories that + dynamically merge the information from multiple databases, services, applications, and other JCR repositories. Another is to + create customized views based upon the type of data and the role of the user that is accessing the data. And yet another is + to create a REST-ful API to allow the JCR content to be accessed easily by other applications written in other languages. + </para> + <para> + The + <link linkend="understanding_dna">next chapter</link> + in this book goes into more detail about JBoss DNA and its architecture, the different components, what's available now, and + what's coming in future releases. + <link linkend="downloading_and_running">Chapter 3</link> + then provides instructions for downloading and running the sequencer examples for the current release. + <link linkend="using_dna">Chapter 4</link> + walks through how to use JBoss DNA in your applications, while + <link linkend="custom_sequencers">Chapter 5</link> + goes over how to create custom sequencers. Finally, + <link linkend="future">Chapter 6</link> + wraps things up with a discussion about the future of JBoss DNA. + </para> +</chapter> Added: trunk/docs/gettingstarted/src/main/docbook/en-US/content/legal_notice.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/content/legal_notice.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/content/legal_notice.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,57 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE legalnotice PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> + +<legalnotice id="Legal_Notice"> + <title>Legal Notice</title> + <para> + <address> + <street>1801 Varsity Drive</street> + <city>Raleigh</city>, <state>NC</state><postcode>27606-2072</postcode><country>USA</country> + <phone>Phone: +1 919 754 3700</phone> + <phone>Phone: 888 733 4281</phone> + <fax>Fax: +1 919 754 3701</fax> + <pob>PO Box 13588</pob><city>Research Triangle Park</city>, <state>NC</state><postcode>27709</postcode><country>USA</country> + </address> + </para> + <para> + Copyright <trademark class="copyright"/> 2007 by Red Hat, Inc. This copyrighted material is made available to + anyone wishing to use, modify, copy, or redistribute it subject to the terms and conditions of the + GNU <ulink url="http://www.gnu.org/licenses/lgpl-2.1.html">Lesser General Public License</ulink>, as published + by the Free Software Foundation. + </para> + <para> + Red Hat and the Red Hat "Shadow Man" logo are registered trademarks of Red Hat, Inc. in the United States and other countries. + </para> + <para> + All other trademarks referenced herein are the property of their respective owners. + </para> + <para> + The GPG fingerprint of the security(a)redhat.com key is: + </para> + <para> + CA 20 86 86 2B D6 9D FC 65 F6 EC C4 21 91 80 CD DB 42 A6 0E + </para> +</legalnotice> Added: trunk/docs/gettingstarted/src/main/docbook/en-US/content/preface.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/content/preface.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/content/preface.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,49 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE preface PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> +<preface id="preface" revision="1"> + <title>What this book covers</title> + <para>The goal of this book is to help you learn about JBoss DNA and how you can use it in your own applications to get the + most out of your JCR repositories.</para> + <para>The first part of the book starts out with an introduction to content repositories and an overview of the JCR API, + both of which are important aspects of JBoss DNA. This is followed by an overview of the JBoss DNA project, its + architecture, and a basic roadmap for what's coming next.</para> + <para>The next part of the book covers how to download and build the examples, how to use JBoss DNA with existing + repositories, and how to build and use custom sequencers.</para> + <para> + If you have any questions or comments, please feel free to contact JBoss DNA's + <ulink url="mailto:dna-users@jboss.org">user mailing list</ulink> + or use the + <ulink url="http://www.jboss.com/index.html?module=bb&amp;op=viewforum&... forums</ulink> + . If you'd like to get involved on the project, join the + <ulink url="http://www.jboss.org/dna/lists.html">mailing lists</ulink> + , + <ulink url="http://www.jboss.org/dna/subversion.html">download the code</ulink> + and get it building, and visit our + <ulink url="http://jira.jboss.org/jira/browse/DNA">JIRA issue management system</ulink> + . If there's something in particular you're interested in, talk with the community - there may be others interested in the + same thing. + </para> +</preface> Added: trunk/docs/gettingstarted/src/main/docbook/en-US/content/understanding_dna.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/content/understanding_dna.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/content/understanding_dna.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,525 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> +<chapter id="understanding_dna"> + <title>Understanding JBoss DNA</title> + <sect1 id="jboss_dna_overview"> + <title>Overview</title> + <para>JBoss DNA is a repository and set of tools that make it easy to capture, version, analyze, and understand the + fundamental building blocks of information. As models, service and process definitions, schemas, source code, and other + artifacts are added to the repository, JBoss DNA "sequences" the makeup of these components and extracts their structure + and interdependencies. The JBoss DNA web application allows end users to access, visualize, and edit this information in + the terminology and structure they are familiar with. Such domain-specific solutions can be easily created with little or + no programming.</para> + <para> JBoss DNA supports the Java Content Repository (JCR) standard and is able to provide a single integrated view of + multiple repositories, external databases, services, and applications, ensuring that JBoss DNA has access to the latest + and most reliable master data. For instance, DNA could provide in a single view valuable insight into the business + processes and process-level services impacted by a change to in an intermediary web server operation defined via WSDL. + Similarly, a user could quickly view and navigate the dependencies between the data source models and transformation + information stored within a content repository, the code base stored within a version control system, and the database + schemas used by an application.</para> + </sect1> + <sect1 id="architecture"> + <title>Architecture</title> + <para>The architecture for JBoss DNA consists of several major components that will be built on top of standard APIs, + including JCR, JDBC, JNDI and HTTP. The goal is to allow these components to be assembled as needed and add value on top + of other DNA components or third-party systems that support these standard APIs.</para> + <mediaobject> + <imageobject role="fo"> + <imagedata align="center" fileref="images/dna-architecture.png" /> + </imageobject> + <imageobject role="html"> + <imagedata align="center" fileref="images/dna-architecture.png" /> + </imageobject> + </mediaobject> + <para> + As shown in the diagram above, the major components are (starting at the top): + <itemizedlist> + <listitem> + <para> + <emphasis role="strong">DNA Eclipse Plugins</emphasis> + enable Eclipse users to access the contents of a JBoss DNA repository. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA JDBC Driver</emphasis> + provides a driver implementation, allowing JDBC-aware applications to connect to and use a JBoss DNA repository. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA Remote JCR</emphasis> + is a client-side component for accessing remote JCR repositories. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA Web Application</emphasis> + is used by end users and domain experts to visualize, search, edit, change and tag the repository content. The web + application uses views to define how different types of information are to be presented and edited in + domain-specific ways. The goal is that this web application is easily customized and branded for inclusion into + other solutions and application systems. The DNA Web Application operates upon any JCR-compliant repository, + although it does rely upon the DNA analysis and templating services. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA Publishing Server</emphasis> + allows content to be downloaded, uploaded, and edited using the Atom Publishing Protocol. With the DNA Publishing + Server, the content of the repository can easily be created, read, edited, and deleted using the standard HTTP + operations of POST, GET, PUT, and DELETE (respectively). More and more tools are being created that support working + with Atom Publishing servers. The DNA Publishing Server operates upon any JCR-compliant repository. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA WebDAV Server</emphasis> + allows clients such as Microsoft Windows and Apple OS X to connect to, read, and edit the content in the repository + using the WebDAV standard. Since WebDAV is an extension of HTTP, web browsers are able to read (but not modify) the + content served by a WebDAV compliant server. The DNA WebDAV Server operates upon any JCR-compliant repository. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA Sequencers</emphasis> + are pluggable components that make it possible for content to be uploaded to the repository and automatically + processed to extract meaningful structure and place that structure in the repository. Once this information is in + the repository, it can be viewed, edited, analyzed, searched, and related to other content. DNA defines a Java + interface that sequencers must implement. DNA sequencers operate upon any JCR-compliant repository. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA Analyses</emphasis> + are pluggable components that analyze content and the relationships between content to generate reports or to answer + queries. DNA will include some standard analyzers, like dependency analysis and similarity analysis, that are + commonly needed by many different solutions. DNA analyzers operate upon any JCR-compliant repository. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA Views</emphasis> + are definitions of how types of information are to be presented in a user interface to allow for creation, reading, + editing, and deletion of information. DNA view definitions consist of data stored in a JCR repository, and as such + views can be easily added, changed or removed entirely by using the DNA Web Application, requiring no programming. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA Federation</emphasis> + is an implementation of the JCR API that builds the content within the repository by accessing and integrating + information from multiple sources. DNA Federation allows the integration of external systems, like other JCR + repositories, databases, applications, and services. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA Connectors</emphasis> + are used to communicate with these external sources of information. In the federation engine, each source is able to + contribute node structure and node properties to any part of the federated graph, although typically many connectors + will contribute most of their information to isolated subgraphs. The result is that integration from a wide range of + systems can be integrated and accessed through the DNA Web Application, DNA Publishing Server, and DNA WebDAV + Server. Connectors also may optionally participate in distributed transactions by exposing an XAResource. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">DNA Maven</emphasis> + is a classloader library compatible with Maven 2 project dependencies. This allows the creation of Java ClassLoader + instances using Maven 2 style paths, and all dependencies are transitively managed and included. + </para> + </listitem> + </itemizedlist> + </para> + <para> + Continue reading the rest of this chapter for more detail about the + <link linkend="sequencers">sequencing framework</link> + available in this release, or the + <link linkend="federation">federation engine</link> + and + <link linkend="federation_connectors">connectors</link> + that will be the focus of the next release. Or, skip to the + <link linkend="downloading_and_running">examples</link> + to see how to start using JBoss DNA &versionNumber; + today. + </para> + </sect1> + <sect1 id="sequencers"> + <title>Sequencing content</title> + <para> The current JBoss DNA release contains a sequencing framework that is designed to sequence data (typically files) + stored in a JCR repository to automatically extract meaningful and useful information. This additional information is then + saved back into the repository, where it can be accessed and used.</para> + <para> In other words, you can just upload various kinds of files into a JCR repository, and DNA automatically processes + those files to extract meaningful structured information. For example, load DDL files into the repository, and let + sequencers extract the structure and metadata for the database schema. Load Hibernate configuration files into the + repository, and let sequencers extract the schema and mapping information. Load Java source into the repository, and let + sequencers extract the class structure, JavaDoc, and annotations. Load a PNG, JPEG, or other image into the repository, + and let sequencers extract the metadata from the image and save it in the repository. The same with XSDs, WSDL, WS + policies, UML, MetaMatrix models, etc.</para> + <para> + JBoss DNA sequencers sit on top of existing JCR repositories (including federated repositories) - they basically extract + more useful information from what's already stored in the repository. And they use the existing JCR versioning system. Each + sequencer typically processes a single kind of file format or a single kind of content. </para> + <para>The following sequencers are included in JBoss DNA: + <itemizedlist> + <listitem> + <para> + <emphasis role="strong">Image sequencer</emphasis> + - A sequencer that processes the binary content of an image file, extracts the metadata for the image, and then + writes that image metadata to the repository. It gets the file format, image resolution, number of bits per pixel + (and optionally number of images), comments and physical resolution from JPEG, GIF, BMP, PCX, PNG, IFF, RAS, PBM, + PGM, PPM, and PSD files. (This sequencer may be improved in the future to also extract EXIF metadata from JPEG + files; see + <ulink url="http://jira.jboss.org/jira/browse/DNA-26">DNA-26</ul... + .) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">MP3 sequencer</emphasis> + - A sequencer that processes the contents of an MP3 audio file, extracts the metadata for the file, and then + writes that image metadata to the repository. It gets the title, author, album, year, and comment. + (This sequencer may be improved in the future to also extract other ID3 metadata from other audio file formats; see + <ulink url="http://jira.jboss.org/jira/browse/DNA-66">DNA-26</ul... + .) + </para> + </listitem> + </itemizedlist> + </para> + <para> + As the community develops additional sequencers, they will also be included in JBoss DNA. Some of those that have been + identified as being useful include: + <itemizedlist> + <listitem> + <para> + <emphasis role="strong">XML Schema Document (XSD) Sequencer</emphasis> + - Process XSD files and extract the various elements, attributes, complex types, simple types, groups, and other + information. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-32">DNA-32</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">Web Service Definition Language (WSDL) Sequencer</emphasis> + - Process WSDL files and extract the services, bindings, ports, operations, parameters, and other information. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-33">DNA-33</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">Hibernate File Sequencer</emphasis> + - Process Hibernate configuration (cfg.xml) and mapping (hbm.xml) files to extract the configuration and mapping + information. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-61">DNA-61</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">XML Metadata Interchange (XMI) Sequencer</emphasis> + - Process XMI documents that contain UML models or models using another metamodel, extracting the model structure + into the repository. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-31">DNA-31</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">ZIP Archive Sequencer</emphasis> + - Process ZIP archive files to extract (explode) the contents into the repository. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-63">DNA-63</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">Java Archive (JAR) Sequencer</emphasis> + - Process JAR files to extract (explode) the contents into the classes and file resources. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-64">DNA-64</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">Java Class File Sequencer</emphasis> + - Process Java class files (bytecode) to extract the class structure (including annotations) into the repository. + (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-62">DNA-62</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">Java Source File Sequencer</emphasis> + - Process Java source files to extract the class structure (including annotations) into the repository. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-51">DNA-51</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">PDF Sequencer</emphasis> + - Process PDF files to extract the document metadata, including table of contents. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-50">DNA-50</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">Maven 2 POM Sequencer</emphasis> + - Process Maven 2 Project Object Model (POM) files to extract the project information, dependencies, plugins, and + other content. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-24">DNA-24</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">Data Definition Language (DDL) Sequencer</emphasis> + - Process various dialects of DDL, including that from Oracle, SQL Server, MySQL, PostgreSQL, and others. May need + to be split up into a different sequencer for each dialect. (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-26">DNA-26</ul... + ) + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">MP3 and MP4 Sequencer</emphasis> + - Process MP3 and MP4 audio files to extract the name of the song, artist, album, track number, and other metadata. + (See + <ulink url="http://jira.jboss.org/jira/browse/DNA-30">DNA-30</ul... + ) + </para> + </listitem> + </itemizedlist> + </para> + <para> + The + <link linkend="using_dna">examples</link> + in this book go into more detail about how sequencers are managed and used, and + <link linkend="custom_sequencers">Chapter 5</link> + goes into detail about how to write custom sequencers. + </para> + </sect1> + <sect1 id="federation"> + <title>Federating content</title> + <para>There is a lot of information stored in many of different places: databases, repositories, SCM systems, + registries, file systems, services, etc. The purpose of the federation engine is to allow applications to use the JCR API + to access that information as if it were all stored in a single JCR repository, but to really leave the information where + it is.</para> + <para>Why not just move the information into a JCR repository? Most likely there are existing applications that rely upon + that information being where it is. If we were to move it, then all those applications would break. Or they'd have to be + changed to use JCR. If the information is being used, the most practical thing is to leave it where it is.</para> + <para> + Then why not just copy the information into a JCR repository? Actually, there are times when it's perfectly reasonable to + make a copy of the data. Perhaps the system managing the existing information cannot handle the additional load of more + clients. Or, perhaps the information doesn't change, or it does change and we want snapshots that don't change. But more + likely, the data + <emphasis>does</emphasis> + change. So if applications are to use the most current information and we make copies of the data, we have to keep the + copies synchronized with the master. That's generally a lot of work. + </para> + <para>The JBoss DNA federation engine lets us leave the information where it is, yet lets client applications use the JCR + API to access all the information without caring where the information really exists. If the underlying information + changes, client applications using JCR observation will be notified of the changes. If a JBoss DNA federated repository is + configured to allow updates, client applications can change the information in the repository and JBoss DNA will propagate + those changes down to the original source.</para> + <sect2 id="federation_connectors"> + <title>Connecting to information sources</title> + <para> + The JBoss DNA federation engine will use connectors to interact with different information sources to get at the content + in those systems. Some ideas for connectors include: + <itemizedlist> + <listitem> + <para> + <emphasis role="strong">JCR Repository Connector</emphasis> + - Connect to and interact with other JCR repositories. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">File System Connector</emphasis> + - Expose the files and directories on a file system through JCR. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">Maven 2 Repository Connector</emphasis> + - Access and expose the contents of a Maven 2 repository (either on the local file system or via HTTP) through + JCR. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">JDBC Metadata Connector</emphasis> + - Connect to relational databases via JDBC and expose their schema as content in a repository. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">UDDI Connector</emphasis> + - Interact with UDDI registries to integrate their content into a repository. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">SVN Connector</emphasis> + - Interact with Subversion software configuration management (SCM) repositories to expose the managed resources + through JCR. Consider using the + <ulink url="http://svnkit.com/">SVNkit</ulink> + (dual license) library for an API into Subversion. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">CVS Connector</emphasis> + - Interact with CVS software configuration management (SCM) repositories to expose the managed resources through + JCR. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">JDBC Storage Connector</emphasis> + - Store and access information in a relational database. Also useful for persisting information in the federated + repository not stored elsewhere. + </para> + </listitem> + <listitem> + <para> + <emphasis role="strong">Distributed Database Connector</emphasis> + - Store and access information in a + <ulink url="http://www.hypertable.org/">Hypertable</ulink> + or + <ulink url="http://hadoop.apache.org/hbase/">HBase</ulink> + distributed databases. Also useful for persisting information in the federated repository not stored elsewhere. + </para> + </listitem> + </itemizedlist> + </para> + <para> + If the connectors allow the information they contribute to be updated, they must provide an + <code>XAResource</code> + implementation that can be used with a Java Transaction Service. Connectors that provide read-only access need not + provide an implementation. + </para> + <para> + Also, connectors talk to + <emphasis>sources</emphasis> + of information, and it's quite likely that the same connector is used to talk to different sources. Each source contains + the configuration details (e.g., connection information, location, properties, options, etc.) for working with that + particular source, as well as a reference to the connector that should be used to establish connections to the source. + And of course, sources can be added or removed without having to stop and restart the federated repository. + </para> + </sect2> + <sect2 id="federation_graph"> + <title>Building the unified graph</title> + <para> The federation engine works by effectively building up a single graph by querying each source and merging or + unifying the responses. This information is cached, which improves performance, reduces the number of (potentially + expensive) remote calls, reduces the load on the sources, and helps mitigate problems with source availability. As + clients interact with the repository, this cache is consulted first. When the requested portion of the graph (or + "subgraph") is contained completely in the cache, it is retuned immediately. However, if any part of the requested + subgraph is not in the cache, each source is consulted for their contributions to that subgraph, and any results are + cached.</para> + <para> This basic flow makes it possible for the federated repository to build up a local cache of the integrated graph + (or at least the portions that are used by clients). In fact, the federated repository caches information in a manner + that is similar to that of the Domain Name System (DNS). As sources are consulted for their contributions, the source + also specifies whether it is the authoritative source for this information (some sources that are themselves federated + may not be the information's authority), whether the information may be modified, the time-to-live (TTL) value (the time + after which the cached information should be refreshed), and the expiration time (the time after which the cached + information is no longer valid). In effect, the source has complete control over how the information it contributes is + cached and used.</para> + <para> + The federated repository also needs to incorporate + <emphasis>negative caching</emphasis> + , which is storage of the knowledge that something does not exist. Sources can be configured to contribute information + only below certain paths (e.g., + <code>/A/B/C</code> + ), and the federation engine can take advantage of this by never consulting that source for contributions to information + on other paths. However, below that path, any negative responses must also be cached (with appropriate TTL and expiry + parameters) to prevent the exclusion of that source (in case the source has information to contribute at a later time) + or the frequent checking with the source. + </para> + </sect2> + <sect2 id="federation_queries"> + <title>Searching and querying</title> + <para> The JBoss DNA federated repository will also support queries against the integrated and unified graph. In some + situations the query can be determined to apply to a single source, but in most situations the query must be planned + (and possibly rewritten) such that it can be pushed down to all the appropriate sources. Also, the cached results must + be consulted prior to returning the query results, as the results from one source might have contributions from another + source.</para> + <note> + <para> It is hoped that the MetaMatrix query engine can be used for this purpose after it is open-sourced. This engine + implements sophisticated query planning and optimization techniques for working efficiently with multiple sources. + </para> + </note> + <para>Searching the whole federated repository is also important. This allows users to simply supply a handful of + search terms, and to get results that are ranked based upon how close each result is to the search terms. (Searching is + very different from querying, which involves specifying the exact semantics of what is to be searched and how the + information is to be compared.) JBoss DNA will incorporate a search engine (e.g., likely to be Lucene) and will populate + the engine's indexes using the federated content and the cached information. Notifications of changing information will + be reflected in the indexes, but some sources may want to explicitly allow or disallow periodic crawling of their + content.</para> + </sect2> + <sect2 id="federation_updates"> + <title>Updating content</title> + <para> + The JBoss DNA federated repositories also make it possible for client applications to make changes to the unified graph + within the context of distributed transactions. According to the JCR API, client applications use the Java Transaction + API (JTA) to control the boundaries of their transactions. Meanwhile, the federated repository uses a + <ulink url="http://www.jboss.org/jbosstm/">distributed transaction service</ulink> + to coordinate the XA resources provided by the connectors. + </para> + <para> It is quite possible that clients add properties to nodes in the unified graph, and that this information cannot be + handled by the same underlying source that contributed to the node. In this case, the federated repository can be + configured with a fallback source that will be used used to store this "extra" information.</para> + <para> + It is a goal that non-XA sources (i.e., sources that use connectors without XA resources) can participate in distributed + transactions through the use of + <emphasis>compensating transactions</emphasis> + . Because the JBoss DNA federation engine implements the JCR observation system, it is capable of recording all of the + changes made to the distributed graph (and those changes sent to each updatable source). Therefore, if a non-XA source + is involved in a distributed transaction that must be rolled back, any changes made to non-XA sources can be undone. (Of + course, this does not make the underlying source transactional: non-transactional sources still may expose the interim + changes to other clients.) + </para> + </sect2> + <sect2 id="federation_events"> + <title>Observing changes</title> + <para> The JCR API supports observing a repository to receive notifications of additions, changes and deletions of nodes + and properties. The JBoss DNA federated repository will support this API through two primary means.</para> + <para> When the changes are made through the federated repository, the JBoss DNA federation engine is well aware of the + set of changes that have been (or are being) made to the unified graph. These events are directly propagated to + listeners.</para> + <para> Sources have the ability to publish events, making it possible for the JBoss DNA federation engine and clients that + have registered listeners to be notified of changes in the information managed by that source. These events are first + processed by the federation engine and possibly altered based upon contributions from other sources. (The federation + engine also uses these events to update or purge information in the cache, which may add to the event set.) The + resulting (and possibly altered) event set is then sent to all client listeners.</para> + </sect2> + </sect1> +</chapter> Added: trunk/docs/gettingstarted/src/main/docbook/en-US/content/using_dna.xml =================================================================== --- trunk/docs/gettingstarted/src/main/docbook/en-US/content/using_dna.xml (rev 0) +++ trunk/docs/gettingstarted/src/main/docbook/en-US/content/using_dna.xml 2008-09-04 17:44:52 UTC (rev 497) @@ -0,0 +1,448 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- + ~ JBoss, Home of Professional Open Source. + ~ + ~ Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as + ~ indicated by the @author tags or express copyright attribution + ~ statements applied by the authors. All third-party contributions are + ~ distributed under license by Red Hat Middleware LLC. + ~ + ~ This copyrighted material is made available to anyone wishing to use, modify, + ~ copy, or redistribute it subject to the terms and conditions of the GNU + ~ Lesser General Public License, as published by the Free Software Foundation. + ~ + ~ This program is distributed in the hope that it will be useful, + ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License + ~ for more details. + ~ + ~ You should have received a copy of the GNU Lesser General Public License + ~ along with this distribution; if not, write to: + ~ Free Software Foundation, Inc. + ~ 51 Franklin Street, Fifth Floor + ~ Boston, MA 02110-1301 USA + --> +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> +<chapter id="using_dna"> + <title>Using JBoss DNA</title> + <para>As we've mentioned before, JBoss DNA is able to work with existing JCR repositories. Your client applications + make changes to the information in those repositories, and JBoss DNA automatically uses its sequencers to extract + additional information from the uploaded files.</para> + <note> + <para>Configuring JBoss DNA sequencers is a bit more manual than is ideal. As you'll see, JBoss DNA uses dependency + injection to allow a great deal of flexibility in how it can be configured and customized. However, the next release will + provide a much easier mechanism for configuring not only the sequencer service but also the upcoming federation engine and + JCR implementation.</para> + </note> + <sect1 id="sequencing_service"> + <title>Configuring the Sequencing Service</title> + <para>The JBoss DNA <emphasis>sequencing service</emphasis> is the component that manages the <emphasis>sequencers</emphasis>, + reacting to changes in JCR repositories and then running the appropriate sequencers. + This involves processing the changes on a node, determining which (if any) sequencers should be run on that node, + and for each sequencer constructing the execution environment, calling the sequencer, and saving the information + generated by the sequencer.</para> + <para>To set up the sequencing service, an instance is created, and dependent components are injected into + the object. This includes among other things: + <itemizedlist> + <listitem> + <para>An <emphasis>execution context</emphasis> that defines the context in which the service runs, including + a factory for JCR sessions given names of the repository and workspace. This factory must be configured, + and is how JBoss DNA knows about your JCR repositories and how to connect to them. More on this a bit later.</para> + </listitem> + <listitem> + <para>An optional <emphasis>factory for class loaders</emphasis> used to load sequencers. If no factory is supplied, + the service uses the current thread's context class loader (or if that is null, the class loader that loaded the + sequencing service class).</para> + </listitem> + <listitem> + <para>An <code>java.util.concurrent.ExecutorService</code> used to execute the sequencing activites. If none + is supplied, a new single-threaded executor is created by calling <code>Executors.newSingleThreadExecutor()</code>. + (This can easily be changed by subclassing and overriding the <code>SequencerService.createDefaultExecutorService()</code> method.)</para> + </listitem> + <listitem> + <para>Filters for sequencers and events. By default, all sequencers are considered for "node added", "property added" + and "property changed" events.</para> + </listitem> + </itemizedlist> + </para> + <para>As mentioned above, the <code>ExecutionContext</code> provides access to a <code>SessionFactory</code> that is used + by JBoss DNA to establish sessions to your JCR repositories. Two implementations are available: + <itemizedlist> + <listitem> + <para>The <code>JndiSessionFactory</code> looks up JCR <code>Repository</code> instances in JNDI using + names that are supplied when creating sessions. This implementation also has methods to set the + JCR <code>Credentials</code> for a given workspace name.</para> + </listitem> + <listitem> + <para>The <code>SimpleSessionFactory</code> has methods to register the JCR <code>Repository</code> instances + with names, as well as methods to set the JCR <code>Credentials</code> for a given workspace name.</para> + </listitem> + </itemizedlist> + You can use the <code>SimpleExecutionContext</code> implementation of <code>ExecutionContext</code> and supply + a <code>SessionFactory</code> instance, or you can provide your own implementation.</para> + <para>Here's an example of how to instantiate and configure the SequencingService:</para> + <programlisting role="JAVA"><![CDATA[ +SimpleSessionFactory sessionFactory = new SimpleSessionFactory(); +sessionFactory.registerRepository("Main Repository", this.repository); +Credentials credentials = new SimpleCredentials("jsmith", "secret".toCharArray()); +sessionFactory.registerCredentials("Main Repository/Workspace1", credentials); +ExecutionContext executionContext = new SimpleExecutionContext(sessionFactory); + +// Create the sequencing service, passing in the execution context ... +SequencingService sequencingService = new SequencingService(); +sequencingService.setExecutionContext(executionContext); + ]]></programlisting> + <para>After the sequencing service is created and configured, it must be started. The SequencingService + has an <emphasis>administration object</emphasis> (that is an instance of <code>ServiceAdministrator</code>) + with <code>start()</code>, <code>pause()</code>, and <code>shutdown()</code> methods. The latter method will + close the queue for sequencing, but will allow sequencing operations already running to complete normally. + To wait until all sequencing operations have completed, simply call the <code>awaitTermination</code> method + and pass it the maximum amount of time you want to wait.</para> + <programlisting role="JAVA"><![CDATA[sequencingService.getAdministrator().start(); +]]></programlisting> + <para>The sequencing service must also be configured with the sequencers that it will use. This is done using the + <code>addSequencer(SequencerConfig)</code> method and passing a <code>SequencerConfig</code> instance that + you create. Here's an example:</para> + <programlisting role="JAVA"><![CDATA[ +String name = "Image Sequencer"; +String desc = "Sequences image files to extract the characteristics of the image"; +String classname = "org.jboss.dna.sequencer.images.ImageMetadataSequencer"; +String[] classpath = null; // Use the current classpath +String[] pathExpressions = {"//(*.(jpg|jpeg|gif|bmp|pcx|png))[*]/jcr:content[@jcr:data] => /images/$1"}; +SequencerConfig imageSequencerConfig = new SequencerConfig(name, desc, classname, + classpath, pathExpressions); +sequencingService.addSequencer(imageSequencerConfig); + +name = "Mp3 Sequencer"; +desc = "Sequences mp3 files to extract the id3 tags of the audio file"; +classname = "org.jboss.dna.sequencer.mp3.Mp3MetadataSequencer"; +String[] mp3PathExpressions = {"//(*.mp3)[*]/jcr:content[@jcr:data] =&gt; /mp3s/$1"}; +SequencerConfig mp3SequencerConfig = new SequencerConfig(name, desc, classname, + classpath, mp3PathExpressions); +sequencingService.addSequencer(mp3SequencerConfig); + ]]></programlisting> + <para>This is pretty self-explanatory, except for the <code>classpath</code> and <code>pathExpression</code> parameters. + The classpath parameter defines the classpath that is passed to the class loader factory mentioned above. + Our sequencer is on the classpath, so we can simply use <code>null</code> here.</para> + <para>The path expression is more complicated. Sequencer path expressions are used by the sequencing service to + determine whether a particular changed node should be sequenced. The expressions consist of two parts: a selection + criteria and an output expression:</para> + <programlisting><![CDATA[ inputPath => outputPath ]]></programlisting> + <para>The <emphasis>inputPath</emphasis> part defines an expression for the path that is to change and that should be sequenced. + Input paths must match node names (including same-name-sibling indexes), and can use wildcards in the names and/or indexes. + Wildcards include: + <itemizedlist> + <listitem> + <para>"<code>//</code>" mean any sequence of nodes, regardless of what their names are</para> + </listitem> + <listitem> + <para>"<code>*</code>" means a node with any name and any same-name-sibling index</para> + </listitem> + </itemizedlist> + </para> + <para>The <emphasis>inputPath</emphasis> part defines an expression for the path that is to change and that should be sequenced. + Input paths must match node names (including same-name-sibling indexes), and can use wildcards in the names and/or indexes. + The characters "<code>//</code>" mean any sequence of nodes (regardless of what their names are), and "<code>*</code>" + means a node with any + + + + + while + the <emphasis>outputPath</emphasis> part defines the location where the content generated by the sequencer should be stored.</para> + <para>Here's a simple example:</para> + <programlisting><![CDATA[ /a/b/c@title => /d/e/f ]]></programlisting> + <para>Here, the <code>/a/b/c@title</code> is the selection criteria that applies when the <code>/a/b/c</code> node has a <code>title</code> property + that is added or changed. When the selection criteria matches a change event, the sequencer will be run + and any generated output will be inserted into the repository described by the output expression. In this example, + the generated output would be placed at the <code>/d/e/f</code> node.</para> + <note> + <para>Sequencer path expressions can be fairly complex and may use wildcards, specificy same-name sibling indexes, + provide optional and choice elements, and may capture parts of the selection criteria for use in the output expression. + The path expression used in the image sequencer configuration example above shows a more complex example:</para> + <programlisting><![CDATA[ //(*.(jpg|jpeg|gif|bmp|pcx|png))[*]/jcr:content[@jcr:data] => /images/$1 ]]></programlisting> + <para>This uses "//" to select any node at any level in the repository whose name ends with "." and one of the extensions (e.g., ".jpg", ".jpeg", etc.) + and that has a child node named "jcr:content" that has a "jcr:data" property. It also selects the file name + as the first capture group (the first set of parentheses) for use in the output expression. + In this example, any sequencer output is placed on a node with that same file name under the "/images" node.</para> + <para>Other things are possible, too. For example, the name of the repository/workspace (as used by the <code>SessionFactory</code>) + may be specified at the beginning of the select criteria and/or the output expression. This means it's possible to place + the sequencer output in a different repository than the node being sequenced.</para> + <para>For more detail about sequencer path expressions, see the <code>org.jboss.dna.repository.sequencer.SequencerPathExpression</code> + class and the corresponding <code>org.jboss.dna.repository.sequencer.SequencerPathExpressionTest</code> test case.</para> + </note> + <para>After the service is started, it is ready to start reacting to changes in the repository. But it first + must be wired to the repositories using a listener. This is accomplished using the <code>ObservationService</code> + described in the <link linkend="observation_service">next section</link>.</para> + </sect1> + <sect1 id="observation_service"> + <title>Configuring the Observation Service</title> + <para>The JBoss DNA <code>ObservationService</code> is responsible for listening to one or more JCR repositories + and multiplexing the events to its listeners. Unlike JCR events, this framework embeds in the events the + name of the repository and workspace that can be passed to a <code>SessionFactory</code> to obtain a session + to the repository in which the change occurred. This simple design makes it very easy for JBoss DNA to + concurrently work with multiple JCR repositories.</para> + <para>Configuring an observation service is pretty easy, especially if you reuse the same <code>SessionFactory</code> + supplied to the sequencing service. Here's an example:</para> + <programlisting role="JAVA"><![CDATA[ + this.observationService = new ObservationService(sessionFactory); + this.observationService.getAdministrator().start(); + ]]></programlisting> + <note> + <para>Both <code>ObservationService</code> and <code>SequencingService</code> implement + <code>AdministeredService</code>, which has a <code>ServiceAdministrator</code> used to start, pause, and shutdown the + service. In other words, the lifecycle of the services are managed in the same way.</para> + </note> + <para>After the observation service is started, listeners can be added. The <code>SequencingService</code> implements the required + interface, and so it may be registered directly:</para> + <programlisting role="JAVA"><![CDATA[ + observationService.addListener(sequencingService); + ]]></programlisting> + <para>Finally, the observation service must be wired to monitor one of your JCR repositories. This is done with + one of the <code>monitor(...)</code> methods:</para> + <programlisting role="JAVA"><![CDATA[ + int eventTypes = Event.NODE_ADDED | Event.PROPERTY_ADDED | Event.PROPERTY_CHANGED; + observationService.monitor("Main Repository/Workspace1", eventTypes); + ]]></programlisting> + <para>At this point, the observation service is listening to a JCR repository and forwarding the appropriate events + to the sequencing service, which will asynchronously process the changes and sequence the information added to or changed in the repository. + </para> + </sect1> + <sect1 id="shutting_down"> + <title>Shutting down JBoss DNA services</title> + <para>The JBoss DNA services are utilizing resources and threads that must be released before your application is ready to shut down. + The safe way to do this is to simply obtain the <code>ServiceAdministrator</code> for each service (via the <code>getServiceAdministrator()</code> method) + and call <code>shutdown()</code>. As previously mentioned, the shutdown method will simply prevent new work from being processed + and will not wait for existing work to be completed. If you want to wait until the service completes all its work, you must wait + until the service terminates. Here's an example that shows how this is done:</para> + <programlisting role="JAVA"><![CDATA[ +// Shut down the service and wait until it's all shut down ... +sequencingService.getAdministrator().shutdown(); +sequencingService.getAdministrator().awaitTermination(5, TimeUnit.SECONDS); + +// Shut down the observation service ... +observationService.getAdministrator().shutdown(); +observationService.getAdministrator().awaitTermination(5, TimeUnit.SECONDS); + ]]></programlisting> + <para>At this point, we've covered how to configure and use the JBoss DNA services in your application. + The next chapter goes back to the <link linkend="downloading_and_running">sample application</link> to show how all + these pieces fit together.</para> + </sect1> + <sect1 id="example_application_review"> + <title>Reviewing the example application</title> + <para>Recall that the example application consists of a client application that sets up an in-memory JCR repository and + that allows a user to upload files into that repository. The client also sets up the DNA services with an image sequencer so + that if any of the uploaded files are PNG, JPEG, GIF, BMP or other images, DNA will automatically extract the image's + metadata (e.g., image format, physical size, pixel density, etc.) and store that in the repository. Or, if the client uploads + MP3 audio files, the title, author, album, year, and comment are extracted from the audio file and stored in the repository.</para> + <para> + The example is comprised of 3 classes and 1 interface, located in the <code>src/main/java</code> directory:</para> + <programlisting><![CDATA[ + org/jboss/example/dna/sequencers/ConsoleInput.java + /MediaInfo.java + /SequencingClient.java + /UserInterface.java + ]]></programlisting> + <para><code>SequencingClient</code> is the class that contains the main application. <code>MediaInfo</code> is a simple Java object + that encapsulates metadata about a media file (as generated by the sequencer), and used by the client to + pass information to the <code>UserInterface</code>, which is an interface with methods that will be called at runtime to + request data from the user. <code>ConsoleInput</code> is an implementation of this that creates a text user interface, + allowing the user to operate the client from the command-line. We can easily create a graphical implementation of + <code>UserInterface</code> at a later date. We can also create a mock implementation for testing purposes that simulates + a user entering data. This allows us to check the behavior of the client automatically using conventional JUnit test cases, + as demonstrated by the code in the <code>src/test/java</code> directory:</para> + <programlisting><![CDATA[ + org/jboss/example/dna/sequencers/SequencingClientTest.java + /MockUserInterface.java + ]]></programlisting> + <para>If we look at the <code>SequencingClient</code> code, there are a handful of methods that encapsulate the various activities.</para> + <note> + <para>To keep the code shown in this book as readable as possible, some of the comments and error handling have been removed.</para> + </note> + <para>The <code>startRepository()</code> method starts up an in-memory Jackrabbit JCR repository. The bulk of this method is simply + gathering and passing the information required by Jackrabbit. Because Jackrabbit's <code>TransientRepository</code> + implementation shuts down after the last session is closed, the application maintains a session to ensure that the + repository remains open throughout the application's lifetime. And finally, the node type needed by the image sequencer is + registered with Jackrabbit.</para> + <programlisting role="JAVA"><![CDATA[ +public void startRepository() throws Exception { + if (this.repository == null) { + try { + + // Load the Jackrabbit configuration ... + File configFile = new File(this.jackrabbitConfigPath); + String pathToConfig = configFile.getAbsolutePath(); + + // Find the directory where the Jackrabbit repository data will be stored ... + File workingDirectory = new File(this.workingDirectory); + String workingDirectoryPath = workingDirectory.getAbsolutePath(); + + // Get the Jackrabbit custom node definition (CND) file ... + URL cndFile = Thread.currentThread().getContextClassLoader().getResource("jackrabbitNodeTypes.cnd"); + + // Create the Jackrabbit repository instance and establish a session to keep the repository alive ... + this.repository = new TransientRepository(pathToConfig, workingDirectoryPath); + if (this.username != null) { + Credentials credentials = new SimpleCredentials(this.username, this.password); + this.keepAliveSession = this.repository.login(credentials, this.workspaceName); + } else { + this.keepAliveSession = this.repository.login(); + } + + try { + // Register the node types (only valid the first time) ... + Workspace workspace = this.keepAliveSession.getWorkspace(); + JackrabbitNodeTypeManager mgr = (JackrabbitNodeTypeManager)workspace.getNodeTypeManager(); + mgr.registerNodeTypes(cndFile.openStream(), JackrabbitNodeTypeManager.TEXT_X_JCR_CND); + } catch (RepositoryException e) { + if (!e.getMessage().contains("already exists")) throw e; + } + + } catch (Exception e) { + this.repository = null; + this.keepAliveSession = null; + throw e; + } + } +} + ]]></programlisting> + <para>As you can see, this method really has nothing to do with JBoss DNA, other than setting up a JCR repository that JBoss + DNA will use.</para> + <para>The <code>shutdownRepository()</code> method shuts down the Jackrabbit transient repository by closing the "keep-alive session". + Again, this method really does nothing specifically with JBoss DNA, but is needed to manage the JCR repository that JBoss DNA uses.</para> + <programlisting role="JAVA"><![CDATA[ +public void shutdownRepository() throws Exception { + if (this.repository != null) { + try { + this.keepAliveSession.logout(); + } finally { + this.repository = null; + this.keepAliveSession = null; + } + } +} + ]]></programlisting> + <para>The <code>startDnaServices()</code> method first starts the JCR repository (if it was not already started), and proceeds + to create and configure the <code>SequencingService</code> as described <link linkend="sequencing_service">earlier</link>. + This involes setting up the <code>SessionFactory</code> and <code>ExecutionContext</code>, creating the + <code>SequencingService</code> instance, and configuring the image sequencer. The method then continues by setting up the + <code>ObservationService</code> as described <link linkend="observation_service">earlier</link> and starting the service.</para> + <programlisting role="JAVA"><![CDATA[ +public void startDnaServices() throws Exception { + if (this.repository == null) this.startRepository(); + if (this.sequencingService == null) { + + SimpleSessionFactory sessionFactory = new SimpleSessionFactory(); + sessionFactory.registerRepository(this.repositoryName, this.repository); + if (this.username != null) { + Credentials credentials = new SimpleCredentials(this.username, this.password); + sessionFactory.registerCredentials(this.repositoryName + "/" + this.workspaceName, credentials); + } + this.executionContext = new SimpleExecutionContext(sessionFactory); + + // Create the sequencing service, passing in the execution context ... + this.sequencingService = new SequencingService(); + this.sequencingService.setExecutionContext(executionContext); + + // Configure the sequencers. + String name = "Image Sequencer"; + String desc = "Sequences image files to extract the characteristics of the image"; + String classname = "org.jboss.dna.sequencer.images.ImageMetadataSequencer"; + String[] classpath = null; // Use the current classpath + String[] pathExpressions = {"//(*.(jpg|jpeg|gif|bmp|pcx|png|iff|ras|pbm|pgm|ppm|psd))[*]/jcr:content[@jcr:data] => /images/$1"}; + SequencerConfig imageSequencerConfig = new SequencerConfig(name, desc, classname, classpath, pathExpressions); + this.sequencingService.addSequencer(imageSequencerConfig); + + // Set up the MP3 sequencer ... + name = "Mp3 Sequencer"; + desc = "Sequences mp3 files to extract the id3 tags of the audio file"; + classname = "org.jboss.dna.sequencer.mp3.Mp3MetadataSequencer"; + String[] mp3PathExpressions = {"//(*.mp3)[*]/jcr:content[@jcr:data] =&gt; /mp3s/$1"}; + SequencerConfig mp3SequencerConfig = new SequencerConfig(name, desc, classname, classpath, mp3PathExpressions); + this.sequencingService.addSequencer(mp3SequencerConfig); + + // Use the DNA observation service to listen to the JCR repository (or multiple ones), and + // then register the sequencing service as a listener to this observation service... + this.observationService = new ObservationService(this.executionContext.getSessionFactory()); + this.observationService.getAdministrator().start(); + this.observationService.addListener(this.sequencingService); + this.observationService.monitor(this.repositoryName + "/" + this.workspaceName, Event.NODE_ADDED | Event.PROPERTY_ADDED | Event.PROPERTY_CHANGED); + } + // Start up the sequencing service ... + this.sequencingService.getAdministrator().start(); +} + ]]></programlisting> + <para>The <code>shutdownDnaServices()</code> method is pretty straightforward: it just calls shutdown on each of the services + and waits until they terminate.</para> + <programlisting role="JAVA"><![CDATA[ +public void shutdownDnaServices() throws Exception { + if (this.sequencingService == null) return; + + // Shut down the service and wait until it's all shut down ... + this.sequencingService.getAdministrator().shutdown(); + this.sequencingService.getAdministrator().awaitTermination(5, TimeUnit.SECONDS); + + // Shut down the observation service ... + this.observationService.getAdministrator().shutdown(); + this.observationService.getAdministrator().awaitTermination(5, TimeUnit.SECONDS); +} + ]]></programlisting> + <para>None of the other methods really do anything with JBoss DNA <emphasis>per se</emphasis>. Instead, they merely work with the repository + using the JCR API.</para> + <para>The <code>main</code> method of the <code>SequencingClient</code> class creates a <code>SequencingClient</code> instance, + and passes a new <code>ConsoleInput</code> instance:</para> + <programlisting role="JAVA"><![CDATA[ +public static void main( String[] args ) throws Exception { + SequencingClient client = new SequencingClient(); + client.setRepositoryInformation("repo", "default", "jsmith", "secret".toCharArray()); + client.setUserInterface(new ConsoleInput(client)); +} + ]]></programlisting> + <para>If we look at the <code>ConsoleInput</code> constructor, it starts the repository, the DNA services, and a thread + for the user interface. At this point, the constructor returns, but the main application continues under the user interface thread. + When the user requests to quit, the user interface thread also shuts down the DNA services and JCR repository.</para> + <programlisting role="JAVA"><![CDATA[ +public ConsoleInput( SequencerClient client ) { + try { + client.startRepository(); + client.startDnaServices(); + + System.out.println(getMenu()); + Thread eventThread = new Thread(new Runnable() { + private boolean quit = false; + public void run() { + try { + while (!quit) { + // Display the prompt and process the requested operation ... + } + } finally { + try { + // Terminate ... + client.shutdownDnaServices(); + client.shutdownRepository(); + } catch (Exception err) { + System.out.println("Error shutting down sequencing service and repository: " + + err.getLocalizedMessage()); + err.printStackTrace(System.err); + } + } + } + }); + eventThread.start(); + } catch (Exception err) { + System.out.println("Error: " + err.getLocalizedMessage()); + err.printStackTrace(System.err); + } +} + ]]></programlisting> + <para>At this point, we've reviewed all of the interesting code in the example application. However, feel free + to play with the application, trying different things.</para> + </sect1> + <sect1 id="using_dna_review"> + <title>Summarizing what we just did</title> + <para>In this chapter we covered the different JBoss DNA components and how they can be used in your application. + Specifically, we described how the <code>SequencingService</code> and <code>ObservationService</code> can + be configured and used. And we ended the chapter by reviewing the example application, which not only uses + JBoss DNA, but also the repository via the JCR API.</para> + </sect1> +</chapter> Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/dna-architecture.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/dna-architecture.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/dna-logo.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/dna-logo.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-cli-client.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-cli-client.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-search-with-mp3.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-search-with-mp3.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-search.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-search.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-search2.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-search2.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-statistics.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-statistics.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-statistics2.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-statistics2.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-upload.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-upload.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Added: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-upload2.png =================================================================== (Binary files differ) Property changes on: trunk/docs/gettingstarted/src/main/docbook/en-US/images/example-sequencer-upload2.png ___________________________________________________________________ Name: svn:mime-type + application/octet-stream