[jboss-dev-forums] [Design the new POJO MicroContainer] - mc-script - and other stupid ideas

I got a bit bored yesterday so I decided to write an example that shows how easy it is to extend the microctonainer's value system. (Actually the example really shows off JBossXB's xml any handling). By way of a stupid example, I decided to write a new ValueMetaData that determines its values using the Java6 script engine stuff. (As usual change svn to anonsvn if you don't have a jboss.org account). https://svn.jboss.org/repos/jbossas/projects/mc-script/trunk/src/main/jav... You should be able to work out how to use it from the xsd https://svn.jboss.org/repos/jbossas/projects/mc-script/trunk/src/main/res... or the tests https://svn.jboss.org/repos/jbossas/projects/mc-script/trunk/src/test/res... Here I'll explain how it works. The extension point is that a property (or parameter or collection element) configuration takes any ValueMetadata because it is defined in the xml to be an xsd:any element. Using the JBossXB annotations to define an xml group (you don't actually need the group, a plain type with a getter/setter marked @XmlAnyElement will also work if it is not of type DOM element) | @JBossXmlGroup | ({ | @JBossXmlChild(name="array", type=AbstractArrayMetaData.class), | @JBossXmlChild(name="collection", type=AbstractCollectionMetaData.class), | @JBossXmlChild(name="inject", type=AbstractInjectionValueMetaData.class), | @JBossXmlChild(name="list", type=AbstractListMetaData.class), | @JBossXmlChild(name="map", type=AbstractMapMetaData.class), | @JBossXmlChild(name="null", type=AbstractValueMetaData.class), | @JBossXmlChild(name="set", type=AbstractSetMetaData.class), | @JBossXmlChild(name="this", type=ThisValueMetaData.class), | @JBossXmlChild(name="value", type=StringValueMetaData.class), | @JBossXmlChild(name="value-factory", type= AbstractValueFactoryMetaData.class) | }) | @JBossXmlGroupText(wrapper= StringValueMetaData.class, property="value") | | // HERE! | | @JBossXmlGroupWildcard(wrapper= AbstractValueMetaData.class, property="value") public interface ValueMetaData extends JBossInterface, MetaDataVisitorNode | and in the xsd | | | <xsd:group name="valueGroup"> | | | <snipped/> | | | <xsd:any namespace="##other" processContents="strict"> | | <xsd:annotation> | | <xsd:documentation>An extension value</xsd:documentation> | | </xsd:annotation> | | </xsd:any> | | </xsd:choice> | | </xsd:group> | This means I can create a new subclass of ValueMetaData in its own xml namespace and use it anywhere a "ValueGroup" is defined in the xml (or equivalently a property is of type ValueMetaData - or a collection of them). This is what I've done with the ScriptValueMetaData that invokes a script to determine the value. | @JBossXmlSchema(namespace="urn:jboss:bean-deployer:script:2.0", elementFormDefault=XmlNsForm.QUALIFIED) | @XmlRootElement(name="script") | @XmlType(name="scriptType", propOrder="parameters") | public class ScriptValueMetaData extends AbstractValueMetaData | The example is slightly more complicated than it needs to be since I added an extra feature so you can pass parameters (including injections from other beans) which means it has to handle visiting the children of the metadata (the parameters) and a few other bits and pieces like making the "controllerContext" available as a variable to the script. Without those complications, you can see that all the work is just in getValue(TypeInfo, ClassLoader). There are a number of other places within the microcontainer and deployment or classloader metadata that can be extended in this way, e.g. the classloader requirement/capabilities. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4235282#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...