[dna-commits] DNA SVN: r914 - in trunk: dna-graph/src/main/java/org/jboss/dna/graph/observe and 2 other directories.

Author: rhauch Date: 2009-05-20 16:30:39 -0400 (Wed, 20 May 2009) New Revision: 914 Added: trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Observer.java Modified: trunk/dna-graph/src/main/java/org/jboss/dna/graph/connector/RepositoryContext.java trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/ChangeObserver.java trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/ChangeObservers.java trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Changes.java trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Observable.java trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/package-info.java trunk/dna-graph/src/test/java/org/jboss/dna/graph/connector/test/AbstractConnectorTest.java trunk/dna-repository/src/main/java/org/jboss/dna/repository/RepositoryLibrary.java Log: DNA-252 Complete support for events to the connector framework Additional changes. Modified: trunk/dna-graph/src/main/java/org/jboss/dna/graph/connector/RepositoryContext.java =================================================================== --- trunk/dna-graph/src/main/java/org/jboss/dna/graph/connector/RepositoryContext.java 2009-05-19 20:15:05 UTC (rev 913) +++ trunk/dna-graph/src/main/java/org/jboss/dna/graph/connector/RepositoryContext.java 2009-05-20 20:30:39 UTC (rev 914) @@ -24,6 +24,7 @@ package org.jboss.dna.graph.connector; import org.jboss.dna.graph.ExecutionContext; +import org.jboss.dna.graph.observe.Observer; /** * The context for a repository. This interface need not be implemented by a {@link RepositorySource}, as it is normally provided @@ -47,4 +48,10 @@ */ RepositoryConnectionFactory getRepositoryConnectionFactory(); + /** + * Get the observer that the connector may use to publish changes. + * + * @return the observer, or null if the are no listeners and publishing is not required/requested + */ + Observer getObserver(); } Modified: trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/ChangeObserver.java =================================================================== --- trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/ChangeObserver.java 2009-05-19 20:15:05 UTC (rev 913) +++ trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/ChangeObserver.java 2009-05-20 20:30:39 UTC (rev 914) @@ -38,7 +38,7 @@ * </p> */ @ThreadSafe -public abstract class ChangeObserver { +public abstract class ChangeObserver implements Observer { private final CopyOnWriteArraySet<ChangeSourceReference> sources = new CopyOnWriteArraySet<ChangeSourceReference>(); @@ -155,5 +155,4 @@ return false; } } - } Modified: trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/ChangeObservers.java =================================================================== --- trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/ChangeObservers.java 2009-05-19 20:15:05 UTC (rev 913) +++ trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/ChangeObservers.java 2009-05-20 20:30:39 UTC (rev 914) @@ -24,7 +24,9 @@ package org.jboss.dna.graph.observe; import java.lang.ref.WeakReference; +import java.util.Iterator; import java.util.concurrent.CopyOnWriteArrayList; +import java.util.concurrent.atomic.AtomicBoolean; import net.jcip.annotations.ThreadSafe; import org.jboss.dna.common.util.CheckArg; import org.jboss.dna.common.util.Logger; @@ -35,7 +37,8 @@ @ThreadSafe public class ChangeObservers implements Observable { - private CopyOnWriteArrayList<ObserverReference> observers = new CopyOnWriteArrayList<ObserverReference>(); + private final CopyOnWriteArrayList<ObserverReference> observers = new CopyOnWriteArrayList<ObserverReference>(); + private final AtomicBoolean shutdown = new AtomicBoolean(false); public ChangeObservers() { } @@ -46,7 +49,7 @@ * @see org.jboss.dna.graph.observe.Observable#register(org.jboss.dna.graph.observe.ChangeObserver) */ public boolean register( ChangeObserver observer ) { - if (observer != null && observers.addIfAbsent(new ObserverReference(observer))) { + if (observer != null && !shutdown.get() && observers.addIfAbsent(new ObserverReference(observer))) { observer.registeredWith(this); return true; } @@ -67,6 +70,30 @@ } /** + * Unregister all registered observers, and mark this as no longer accepting new registered observers. + */ + public void shutdown() { + shutdown.set(true); + while (!observers.isEmpty()) { + Iterator<ObserverReference> iter = observers.iterator(); // gets snapshot + observers.clear(); + while (iter.hasNext()) { + ObserverReference reference = iter.next(); + if (reference.get() != null) reference.get().unregisteredWith(this); + } + } + } + + /** + * Determine whether there are any observers at the time this method is called. + * + * @return true if there are currently no observers, or false if there is at least one observer + */ + public boolean isEmpty() { + return observers.isEmpty(); + } + + /** * Broadcast the supplied changes to the registered observers. * * @param changes the changes to broadcast Modified: trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Changes.java =================================================================== --- trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Changes.java 2009-05-19 20:15:05 UTC (rev 913) +++ trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Changes.java 2009-05-20 20:30:39 UTC (rev 914) @@ -23,6 +23,9 @@ */ package org.jboss.dna.graph.observe; +import java.io.Serializable; +import java.util.Iterator; +import java.util.List; import javax.security.auth.Subject; import net.jcip.annotations.Immutable; import org.jboss.dna.graph.property.DateTime; @@ -32,26 +35,109 @@ * A set of changes that were made atomically. Each change is in the form of a frozen {@link ChangeRequest}. */ @Immutable -public interface Changes extends Iterable<ChangeRequest> { +public final class Changes implements Iterable<ChangeRequest>, Comparable<Changes>, Serializable { + private static final long serialVersionUID = 1L; + + private final String processId; + private final Subject subject; + private final String sourceName; + private final DateTime timestamp; + private final List<ChangeRequest> changeRequests; + + public Changes( String processId, + Subject subject, + String sourceName, + DateTime timestamp, + List<ChangeRequest> requests ) { + this.subject = subject; + this.sourceName = sourceName; + this.timestamp = timestamp; + this.changeRequests = requests; + this.processId = processId != null ? processId : ""; + } + /** * Get the user that made these changes. * * @return the user; never null */ - public Subject getUser(); + public Subject getSubject() { + return this.subject; + } /** * Get the name of the source that was changed. * * @return the source name; never null */ - public String getSourceName(); + public String getSourceName() { + return this.sourceName; + } /** * Get the timestamp that the changes were made. All changes within the change set were all made at this instant in time. * * @return the timestamp of the changes; never null */ - public DateTime getTimestamp(); + public DateTime getTimestamp() { + return this.timestamp; + } + + /** + * Get the identifier of the process where these changes originated. This identifier may be useful in preventing feedbacks. + * + * @return the process identifier; never null + */ + public String getProcessId() { + return processId; + } + + /** + * {@inheritDoc} + * + * @see java.lang.Iterable#iterator() + */ + public Iterator<ChangeRequest> iterator() { + return this.changeRequests.iterator(); + } + + /** + * {@inheritDoc} + * + * @see java.lang.Object#hashCode() + */ + @Override + public int hashCode() { + return getTimestamp().hashCode(); + } + + /** + * {@inheritDoc} + * + * @see java.lang.Comparable#compareTo(java.lang.Object) + */ + public int compareTo( Changes that ) { + if (this == that) return 0; + return this.getTimestamp().compareTo(that.getTimestamp()); + } + + /** + * {@inheritDoc} + * + * @see java.lang.Object#equals(java.lang.Object) + */ + @Override + public boolean equals( Object obj ) { + if (obj == this) return true; + if (obj instanceof Changes) { + Changes that = (Changes)obj; + if (!this.getProcessId().equals(that.getProcessId())) return false; + if (!this.getSourceName().equals(that.getSourceName())) return false; + if (!this.getTimestamp().equals(that.getTimestamp())) return false; + if (!this.getSubject().equals(that.getSubject())) return false; + return true; + } + return false; + } } Modified: trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Observable.java =================================================================== --- trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Observable.java 2009-05-19 20:15:05 UTC (rev 913) +++ trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Observable.java 2009-05-20 20:30:39 UTC (rev 914) @@ -36,7 +36,8 @@ * Register the supplied observer. This method does nothing if the observer reference is null. * * @param observer the observer to be added; may be null - * @return true if the observer was added, or false if the observer was null or if the observer was already registered + * @return true if the observer was added, or false if the observer was null, if the observer was already registered, or if + * the observer could not be added */ boolean register( ChangeObserver observer ); Copied: trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Observer.java (from rev 913, trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Changes.java) =================================================================== --- trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Observer.java (rev 0) +++ trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/Observer.java 2009-05-20 20:30:39 UTC (rev 914) @@ -0,0 +1,38 @@ +/* + * JBoss DNA (http://www.jboss.org/dna) + * See the COPYRIGHT.txt file distributed with this work for information + * regarding copyright ownership. Some portions may be licensed + * to Red Hat, Inc. under one or more contributor license agreements. + * See the AUTHORS.txt file in the distribution for a full listing of + * individual contributors. + * + * JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA + * is licensed to you under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * JBoss DNA 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 software; if not, write to the Free + * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA, or see the FSF site: http://www.fsf.org. + */ +package org.jboss.dna.graph.observe; + +/** + * + */ +public interface Observer { + + /** + * Method that is called for each {@link Changes set of changes} from the {@link Observable} instance(s) with which this + * observer is registered. + * + * @param changes the changes that are being published + */ + void notify( Changes changes ); +} Modified: trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/package-info.java =================================================================== --- trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/package-info.java 2009-05-19 20:15:05 UTC (rev 913) +++ trunk/dna-graph/src/main/java/org/jboss/dna/graph/observe/package-info.java 2009-05-20 20:30:39 UTC (rev 914) @@ -87,20 +87,6 @@ * Third, the requests that make up a {@link Changes} instance can actually be replayed. Consider the case of a cache * that is backed by a {@link org.jboss.dna.graph.connector.RepositorySource}, which might use an observer to keep the cache in sync. * As the cache is notified of Changes, the cache can simply replay the changes against its source. - * </p> - * <h3>Change feed and timelines</h3> - * <p> - * While it is often sufficient to register observers and receive notifications of the changes as they occur, it - * is also often useful to be able to ask for the changes that have occurred since some time or date. This allows - * a component to poll for changes or, for example, to catch up on the changes that occurred previous to registering - * an observer. - * </p> - * <p> - * Components that implement {@link Observable} may also implement the {@link ChangeFeed} interface to allow for - * components to {@link ChangeFeed#changesSince(org.jboss.dna.graph.property.DateTime) poll for changes}. The result - * of this method is a {@link ChangeTimeline} object that contains the {@link Changes} as well as the time period during which - * the change sets occurred. Note that an empty {@link ChangeTimeline} object implies there were no changes made during the time period. - * </p> */ package org.jboss.dna.graph.observe; Modified: trunk/dna-graph/src/test/java/org/jboss/dna/graph/connector/test/AbstractConnectorTest.java =================================================================== --- trunk/dna-graph/src/test/java/org/jboss/dna/graph/connector/test/AbstractConnectorTest.java 2009-05-19 20:15:05 UTC (rev 913) +++ trunk/dna-graph/src/test/java/org/jboss/dna/graph/connector/test/AbstractConnectorTest.java 2009-05-20 20:30:39 UTC (rev 914) @@ -51,6 +51,7 @@ import org.jboss.dna.graph.connector.RepositoryContext; import org.jboss.dna.graph.connector.RepositorySource; import org.jboss.dna.graph.connector.RepositorySourceException; +import org.jboss.dna.graph.observe.Observer; import org.jboss.dna.graph.property.DateTime; import org.jboss.dna.graph.property.Name; import org.jboss.dna.graph.property.Path; @@ -123,6 +124,10 @@ public RepositoryConnectionFactory getRepositoryConnectionFactory() { return connectionFactory; } + + public Observer getObserver() { + return null; // no observers here + } }); // And set up the graph instance ... Modified: trunk/dna-repository/src/main/java/org/jboss/dna/repository/RepositoryLibrary.java =================================================================== --- trunk/dna-repository/src/main/java/org/jboss/dna/repository/RepositoryLibrary.java 2009-05-19 20:15:05 UTC (rev 913) +++ trunk/dna-repository/src/main/java/org/jboss/dna/repository/RepositoryLibrary.java 2009-05-20 20:30:39 UTC (rev 914) @@ -41,6 +41,11 @@ import org.jboss.dna.graph.connector.RepositoryConnectionPool; import org.jboss.dna.graph.connector.RepositoryContext; import org.jboss.dna.graph.connector.RepositorySource; +import org.jboss.dna.graph.observe.ChangeObserver; +import org.jboss.dna.graph.observe.ChangeObservers; +import org.jboss.dna.graph.observe.Changes; +import org.jboss.dna.graph.observe.Observable; +import org.jboss.dna.graph.observe.Observer; import org.jboss.dna.repository.mimetype.MimeTypeDetectors; import org.jboss.dna.repository.service.AbstractServiceAdministrator; import org.jboss.dna.repository.service.ServiceAdministrator; @@ -52,7 +57,7 @@ * @author Randall Hauch */ @ThreadSafe -public class RepositoryLibrary implements RepositoryConnectionFactory { +public class RepositoryLibrary implements RepositoryConnectionFactory, Observable { /** * The administrative component for this service. @@ -106,8 +111,9 @@ private final ReadWriteLock sourcesLock = new ReentrantReadWriteLock(); private final CopyOnWriteArrayList<RepositoryConnectionPool> pools = new CopyOnWriteArrayList<RepositoryConnectionPool>(); private RepositoryConnectionFactory delegate; - protected final ExecutionContext executionContext; + private final ExecutionContext executionContext; private final RepositoryContext repositoryContext; + private final ObservationBus observationBus = new InMemoryObservationBus(); /** * Create a new manager instance. @@ -146,11 +152,12 @@ * this manager; may be null if there is no delegate * @throws IllegalArgumentException if the <code>executionContextFactory</code> reference is null */ - public RepositoryLibrary( ExecutionContext executionContext, + public RepositoryLibrary( final ExecutionContext executionContext, RepositoryConnectionFactory delegate ) { CheckArg.isNotNull(executionContext, "executionContext"); this.delegate = delegate; this.executionContext = executionContext; + final ObservationBus observationBus = this.observationBus; this.repositoryContext = new RepositoryContext() { /** * {@inheritDoc} @@ -158,7 +165,7 @@ * @see org.jboss.dna.graph.connector.RepositoryContext#getExecutionContext() */ public ExecutionContext getExecutionContext() { - return RepositoryLibrary.this.executionContext; + return executionContext; } /** @@ -170,10 +177,37 @@ return RepositoryLibrary.this; } + /** + * {@inheritDoc} + * + * @see org.jboss.dna.graph.connector.RepositoryContext#getObserver() + */ + public Observer getObserver() { + return observationBus.hasObservers() ? observationBus : null; + } + }; } /** + * {@inheritDoc} + * + * @see org.jboss.dna.graph.observe.Observable#register(org.jboss.dna.graph.observe.ChangeObserver) + */ + public boolean register( ChangeObserver observer ) { + return observationBus.register(observer); + } + + /** + * {@inheritDoc} + * + * @see org.jboss.dna.graph.observe.Observable#unregister(org.jboss.dna.graph.observe.ChangeObserver) + */ + public boolean unregister( ChangeObserver observer ) { + return observationBus.unregister(observer); + } + + /** * @return executionContextFactory */ public ExecutionContext getExecutionContext() { @@ -235,6 +269,8 @@ } finally { this.sourcesLock.readLock().unlock(); } + // Remove all listeners ... + this.observationBus.shutdown(); } /** @@ -462,4 +498,65 @@ } return null; } + + protected interface ObservationBus extends Observable, Observer { + boolean hasObservers(); + + void shutdown(); + } + + protected class InMemoryObservationBus implements ObservationBus { + private final ChangeObservers observers = new ChangeObservers(); + + protected InMemoryObservationBus() { + } + + /** + * {@inheritDoc} + * + * @see org.jboss.dna.graph.observe.Observable#register(org.jboss.dna.graph.observe.ChangeObserver) + */ + public boolean register( ChangeObserver observer ) { + return observers.register(observer); + } + + /** + * {@inheritDoc} + * + * @see org.jboss.dna.graph.observe.Observable#unregister(org.jboss.dna.graph.observe.ChangeObserver) + */ + public boolean unregister( ChangeObserver observer ) { + return observers.unregister(observer); + } + + /** + * {@inheritDoc} + * + * @see org.jboss.dna.graph.observe.Observer#notify(org.jboss.dna.graph.observe.Changes) + */ + public void notify( Changes changes ) { + if (changes != null) { + // Broadcast the changes to the registered observers ... + observers.broadcast(changes); + } + } + + /** + * {@inheritDoc} + * + * @see org.jboss.dna.repository.RepositoryLibrary.ObservationBus#hasObservers() + */ + public boolean hasObservers() { + return !observers.isEmpty(); + } + + /** + * {@inheritDoc} + * + * @see org.jboss.dna.repository.RepositoryLibrary.ObservationBus#shutdown() + */ + public void shutdown() { + observers.shutdown(); + } + } }