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Craig L Russell commented on JDO-764: ------------------------------------- Do we have any test classes that could easily be adapted to test this capability? We could perhaps define these annotations as one and use in several places in the test cases: @Target(TYPE) @Retention(RUNTIME) @PersistenceCapable(detachable="true", identityType="datastore", embeddedOnly="true") @Inheritance(strategy=InheritanceStrategy.NEW_TABLE) @Discriminator(strategy=DiscriminatorStrategy.CLASS_NAME, column="DISCRIMINATOR", indexed="true") @DatastoreIdentity(strategy=IdGeneratorStrategy.IDENTITY, column="DATASTORE_IDENTITY") @interface @DatastoreIdDiscriminatorPersistable { } Then: @PersistenceCapable(table="persons") @DatastoreIdDiscriminatorPersistable public class FCDSPerson implements IPerson, Serializable, Comparable, Comparator, DeepEquality { Here is additional text to be added to Chapter 19 of the specification. Please review, especially the terminology "compound annotations". Annotations can be combined and applied to user-defined compound annotations. A user-defined annotation itself can be annotated with one or more JDO annotations and when the user-defined annotation is applied to an element, all of its JDO annotations will be applied to that element. > Allow JDO annotations to be used in meta-annotations > ---------------------------------------------------- > > Key: JDO-764 > URL: https://issues.apache.org/jira/browse/JDO-764 > Project: JDO > Issue Type: Improvement > Components: api, specification > Affects Versions: JDO 3.1 > Reporter: Andy Jefferson > Fix For: JDO 3.2 > > Attachments: JDO-764.patch > > > By default annotations are used directly in a persistable class. Java > additionally allows annotations to be formed of other annotations. This is > particularly useful where a user has a particular combination of annotations > to set on a class/field/method and wants to simply annotate with an > abbreviated form. For example, specifying attributes of an annotation > @PersistenceCapable(detachable="true", identityType="datastore", > embeddedOnly="true") > or formed of multiple annotations > @PersistenceCapable(detachable="true") > @Extension(vendorName="datanucleus", key="multitenancy-column-name", > value="TENANT") > These can be represented as meta-annotations like this > @Target(TYPE) > @Retention(RUNTIME) > @PersistenceCapable(detachable="true", identityType="datastore", > embeddedOnly="true") > @interface @DatastoreIdPersistable > { > } > @Target(TYPE) > @Retention(RUNTIME) > @PersistenceCapable(detachable="true") > @Extension(vendorName="datanucleus", key="multitenancy-column-name", > value="TENANT") > @interface @MultitenantPersistable > { > } > and the user can subsequently just annotate their persistable class as > @DatastoreIdPersistable > public class MyClass1 {...} > @MultitenantPersistable > public class MyClass2 {...} > The work required to support this in the JDO spec is simply to update the > following annotations to add @Target({ElementType.ANNOTATION_TYPE}) > The annotations requiring this are > @Element, @EmbeddedId, @Key, @NotPersistent, @Order, @Persistent, > @Serialized, @Transactional, and @Value (all other annotations already have > @Target({ElementType.TYPE}) which already permits their usage in > meta-annotations. > The same is proposed for JPA 2.2, see > https://github.com/javaee/jpa-spec/issues/43 -- This message was sent by Atlassian JIRA (v6.3.15#6346)