| Re: [dali-dev] Listeners in Dali Helios |
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Stefan, JpaProject does not directly hold a collection of entities. Entities can be added or removed from a number of different places within a JpaProject: - They can be listed in the persistence.xml file. - They can be discovered automatically by Dali, when they are annotated. - They can be contained in jar files listed in the persistence.xml file. - They can be listed in mapping files listed in the persistence.xml file. - They can be listed in the implied mapping file (META-INF/orm.xml) even if it is not listed in the persistence.xml file. To reach these objects and listen to them appropriately, you can use the following methods: To get a PersistenceUnit use these methods: JpaProject.getRootContextNode() - this will always be present JpaRootContextNode.getPersistenceXml() - this may null JpaPersistenceXml.getPersistence() - this may null Persistence.persistenceUnit() - this will either be empty or contain a single persistence unit (as Dali only supports a single persistence unit) Once you have a PersistenceUnit, there a number of different objects you need to monitor for entities: - the types listed in the persistence.xml file: PersistenceUnit.specifiedClassRefs() - this may be empty ClassRef.getJavaPersistentType() - this may be null PersistentType.getMappingKey() - this will indicate whether the persistent type is an entity - the types discovered automatically: PersistenceUnit.impliedClassRefs() - this may be empty [see above] - the types in jar files listed in the persistence.xml file: PersistenceUnit.jarFileRefs() - this may be empty JarFileRef.getJarFile() - this maybe null JarFile.javaPersistentTypes() - this may be empty PersistentType.getMappingKey() - this will indicate whether the persistent type is an entity - the types in mapping files listed in the persistence.xml file: PersistenceUnit.specifiedMappingFileRefs() - this may be empty MappingFileRef.getMappingFile() - this may be null, and you will need to check whether it is an instance of OrmXml then cast it OrmXml.getRoot() - this may be null EntityMappings.getPersistentTypes() - this may be empty PersistentType.getMappingKey() - this will indicate whether the persistent type is an entity - the types in the default mapping file: PersistenceUnit.getImpliedMappingFileRef() - this may be empty [see above] So, you will need to listen to a number of objects' changes. For example, to listen for an entity being added or removed via the list of classes in the persistence.xml file: JpaProject added/removed: JpaProjectManager.addCollectionListener(JpaProjectManager.JPA_PROJECTS_COLLECTION, ...) [You can get the JpaProjectManager via the static method JptCorePlugin.getJpaProjectManager().] PersistenceXml added/removed: JpaProject.getRootContextNode().addPropertyChangeListener(JpaRootContextNode.PERSISTENCE_XML_PROPERTY, ...) Persistence added/removed: PersistenceXml.addPropertyChangeListener(PersistenceXml.PERSISTENCE_PROPERTY, ...) PersistenceUnit added/removed: Persistence.addListChangeListener(Persistence.PERSISTENCE_UNITS_LIST, ...) ClassRef added/removed: PersistenceUnit.addListChangeListener(PersistenceUnit.SPECIFIED_CLASS_REFS_LIST,...) PersistentType added/removed: ClassRef.addPropertyChangeListener(ClassRef.JAVA_PERSISTENT_TYPE_PROPERTY, ...) TypeMapping change: PersistentType.addPropertyChangeListener(PersistentType.MAPPING_PROPERTY, ...) Obviously, it is pretty complicated to listen for the adding/removing of entities. I'm not sure I've been exhaustive here, but it should get you started. You might want to use some of our adapters to reduce any bugs and/or listener leaks (e.g. PropertyAspectAdapter). Brian On 06/23/10 10:51, Dimov, Stefan wrote: I have problems with listeners in Helios Dali. I don’t know what kind of listener to add to org.eclipse.jpt.core.JpaProject in order to detect adding and/or removing entities from this project. |