下面列出了怎么用javax.persistence.Inheritance的API类实例代码及写法，或者点击链接到github查看源代码。
private void extractInheritanceType() {
XAnnotatedElement element = getClazz();
Inheritance inhAnn = element.getAnnotation( Inheritance.class );
MappedSuperclass mappedSuperClass = element.getAnnotation( MappedSuperclass.class );
if ( mappedSuperClass != null ) {
setEmbeddableSuperclass( true );
setType( inhAnn == null ? null : inhAnn.strategy() );
}
else {
setType( inhAnn == null ? InheritanceType.SINGLE_TABLE : inhAnn.strategy() );
}
}
private Inheritance getInheritance(Element tree, XMLContext.Default defaults) {
Element element = tree != null ? tree.element( "inheritance" ) : null;
if ( element != null ) {
AnnotationDescriptor ad = new AnnotationDescriptor( Inheritance.class );
Attribute attr = element.attribute( "strategy" );
InheritanceType strategy = InheritanceType.SINGLE_TABLE;
if ( attr != null ) {
String value = attr.getValue();
if ( "SINGLE_TABLE".equals( value ) ) {
strategy = InheritanceType.SINGLE_TABLE;
}
else if ( "JOINED".equals( value ) ) {
strategy = InheritanceType.JOINED;
}
else if ( "TABLE_PER_CLASS".equals( value ) ) {
strategy = InheritanceType.TABLE_PER_CLASS;
}
else {
throw new AnnotationException(
"Unknown InheritanceType in XML: " + value + " (" + SCHEMA_VALIDATION + ")"
);
}
}
ad.setValue( "strategy", strategy );
return AnnotationFactory.create( ad );
}
else if ( defaults.canUseJavaAnnotations() ) {
return getPhysicalAnnotation( Inheritance.class );
}
else {
return null;
}
}
@Test
public void testGetEntityClassFromNodeLabelsHavingTheLabelDeclaredByTheClassNameWithSingleTableInheritance() throws Exception {
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameA = "SubEntityClassA";
final String simpleClassNameB = "SubEntityClassB";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.SINGLE_TABLE);
jBaseClass.annotate(DiscriminatorColumn.class).param("name", "TYPE");
final JDefinedClass jSubclassA = jp._class(JMod.PUBLIC, simpleClassNameA)._extends(jBaseClass);
jSubclassA.annotate(Entity.class);
jSubclassA.annotate(DiscriminatorValue.class).param("value", "A");
final JDefinedClass jSubclassB = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclassB.annotate(Entity.class);
jSubclassB.annotate(DiscriminatorValue.class).param("value", "B");
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> baseClass = loadClass(testFolder.getRoot(), jBaseClass.name());
final Class<?> subClassA = loadClass(testFolder.getRoot(), jSubclassA.name());
final Class<?> subClassB = loadClass(testFolder.getRoot(), jSubclassB.name());
final Class<?> clazz = EntityUtils.getEntityClassFromNodeLabels(Arrays.asList(simpleClassNameBase),
Arrays.asList(baseClass, subClassA, subClassB));
assertThat(clazz, equalTo(baseClass));
}
@Test
public void testGetEntityClassFromNodeLabelsHavingTheLabelDeclaredByTheTableAnnotationWithSingleTableInheritance() throws Exception {
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameA = "SubEntityClassA";
final String simpleClassNameB = "SubEntityClassB";
final String nodeLabel = "ENTITY_CLASS";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Table.class).param("name", nodeLabel);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.SINGLE_TABLE);
jBaseClass.annotate(DiscriminatorColumn.class).param("name", "TYPE");
final JDefinedClass jSubclassA = jp._class(JMod.PUBLIC, simpleClassNameA)._extends(jBaseClass);
jSubclassA.annotate(Entity.class);
jSubclassA.annotate(DiscriminatorValue.class).param("value", "A");
final JDefinedClass jSubclassB = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclassB.annotate(Entity.class);
jSubclassB.annotate(DiscriminatorValue.class).param("value", "B");
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> baseClass = loadClass(testFolder.getRoot(), jBaseClass.name());
final Class<?> subClassA = loadClass(testFolder.getRoot(), jSubclassA.name());
final Class<?> subClassB = loadClass(testFolder.getRoot(), jSubclassB.name());
final Class<?> clazz = EntityUtils.getEntityClassFromNodeLabels(Arrays.asList(nodeLabel),
Arrays.asList(baseClass, subClassA, subClassB));
assertThat(clazz, equalTo(baseClass));
}
@Test
public void testGetEntityClassFromNodeLabelsHavingTheLabelDeclaredByTheClassNameWithTablePerClassInheritance() throws Exception {
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameA = "SubEntityClassA";
final String simpleClassNameB = "SubEntityClassB";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.TABLE_PER_CLASS);
final JDefinedClass jSubclassA = jp._class(JMod.PUBLIC, simpleClassNameA)._extends(jBaseClass);
jSubclassA.annotate(Entity.class);
final JDefinedClass jSubclassB = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclassB.annotate(Entity.class);
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> baseClass = loadClass(testFolder.getRoot(), jBaseClass.name());
final Class<?> subClassA = loadClass(testFolder.getRoot(), jSubclassA.name());
final Class<?> subClassB = loadClass(testFolder.getRoot(), jSubclassB.name());
final Class<?> clazz = EntityUtils.getEntityClassFromNodeLabels(Arrays.asList(simpleClassNameB),
Arrays.asList(baseClass, subClassA, subClassB));
assertThat(clazz, equalTo(subClassB));
}
@Test
public void testGetEntityClassFromNodeLabelsHavingTheLabelDeclaredByTheTableAnnotationWithTablePerClassInheritance() throws Exception {
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameA = "SubEntityClassA";
final String simpleClassNameB = "SubEntityClassB";
final String nodeLabelBase = "ENTITY_CLASS";
final String nodeLabelA = "ENTITY_CLASS_A";
final String nodeLabelB = "ENTITY_CLASS_B";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Table.class).param("name", nodeLabelBase);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.TABLE_PER_CLASS);
final JDefinedClass jSubclassA = jp._class(JMod.PUBLIC, simpleClassNameA)._extends(jBaseClass);
jSubclassA.annotate(Entity.class);
jSubclassA.annotate(Table.class).param("name", nodeLabelA);
final JDefinedClass jSubclassB = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclassB.annotate(Entity.class);
jSubclassB.annotate(Table.class).param("name", nodeLabelB);
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> baseClass = loadClass(testFolder.getRoot(), jBaseClass.name());
final Class<?> subClassA = loadClass(testFolder.getRoot(), jSubclassA.name());
final Class<?> subClassB = loadClass(testFolder.getRoot(), jSubclassB.name());
final Class<?> clazz = EntityUtils.getEntityClassFromNodeLabels(Arrays.asList(nodeLabelA),
Arrays.asList(baseClass, subClassA, subClassB));
assertThat(clazz, equalTo(subClassA));
}
@Test
public void testGetEntityClassFromNodeLabelsHavingTheLabelDeclaredByTheClassNameWithJoinedInheritance() throws Exception {
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameA = "SubEntityClassA";
final String simpleClassNameB = "SubEntityClassB";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.JOINED);
final JDefinedClass jSubclassA = jp._class(JMod.PUBLIC, simpleClassNameA)._extends(jBaseClass);
jSubclassA.annotate(Entity.class);
final JDefinedClass jSubclassB = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclassB.annotate(Entity.class);
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> baseClass = loadClass(testFolder.getRoot(), jBaseClass.name());
final Class<?> subClassA = loadClass(testFolder.getRoot(), jSubclassA.name());
final Class<?> subClassB = loadClass(testFolder.getRoot(), jSubclassB.name());
final Class<?> clazz = EntityUtils.getEntityClassFromNodeLabels(Arrays.asList(simpleClassNameB),
Arrays.asList(baseClass, subClassA, subClassB));
assertThat(clazz, equalTo(subClassB));
}
@Test
public void testGetEntityClassFromNodeLabelsHavingTheLabelDeclaredByTheTableAnnotationWithJoinedInheritance() throws Exception {
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameA = "SubEntityClassA";
final String simpleClassNameB = "SubEntityClassB";
final String nodeLabelBase = "ENTITY_CLASS";
final String nodeLabelA = "ENTITY_CLASS_A";
final String nodeLabelB = "ENTITY_CLASS_B";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Table.class).param("name", nodeLabelBase);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.JOINED);
final JDefinedClass jSubclassA = jp._class(JMod.PUBLIC, simpleClassNameA)._extends(jBaseClass);
jSubclassA.annotate(Entity.class);
jSubclassA.annotate(Table.class).param("name", nodeLabelA);
final JDefinedClass jSubclassB = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclassB.annotate(Entity.class);
jSubclassB.annotate(Table.class).param("name", nodeLabelB);
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> baseClass = loadClass(testFolder.getRoot(), jBaseClass.name());
final Class<?> subClassA = loadClass(testFolder.getRoot(), jSubclassA.name());
final Class<?> subClassB = loadClass(testFolder.getRoot(), jSubclassB.name());
final Class<?> clazz = EntityUtils.getEntityClassFromNodeLabels(Arrays.asList(nodeLabelA),
Arrays.asList(baseClass, subClassA, subClassB));
assertThat(clazz, equalTo(subClassA));
}
@Test
public void testGetNamesOfIdPropertiesFromAClassHierarchyHavingAFieldAnnotatedWithId() throws Exception {
// GIVEN
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameB = "SubEntityClass";
final String idPropertyName = "key";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.TABLE_PER_CLASS);
jBaseClass.field(JMod.PRIVATE, String.class, idPropertyName).annotate(Id.class);
final JDefinedClass jSubclass = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclass.annotate(Entity.class);
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> subClass = loadClass(testFolder.getRoot(), jSubclass.name());
// WHEN
final List<String> namesOfIdProperties = EntityUtils.getNamesOfIdProperties(subClass);
// THEN
assertThat(namesOfIdProperties.size(), equalTo(1));
assertThat(namesOfIdProperties, hasItem(idPropertyName));
}
@Test
public void testGetNamesOfIdPropertiesFromAClassHierarchyHavingAMethodAnnotatedWithId() throws Exception {
// GIVEN
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameB = "SubEntityClass";
final String idPropertyName = "key";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.TABLE_PER_CLASS);
jBaseClass.method(JMod.PUBLIC, jCodeModel.VOID, "getKey").annotate(Id.class);
final JDefinedClass jSubclass = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclass.annotate(Entity.class);
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> subClass = loadClass(testFolder.getRoot(), jSubclass.name());
// WHEN
final List<String> namesOfIdProperties = EntityUtils.getNamesOfIdProperties(subClass);
// THEN
assertThat(namesOfIdProperties.size(), equalTo(1));
assertThat(namesOfIdProperties, hasItem(idPropertyName));
}
@Test
public void testGetNamesOfIdPropertiesFromAClassHierarchyHavingAFieldAnnotatedWithEmbeddedId() throws Exception {
// GIVEN
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameB = "SubEntityClass";
final String compositeIdPropertyName = "compositeKey";
final String id1PropertyName = "key1";
final String id2PropertyName = "key2";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jIdTypeClass = jp._class(JMod.PUBLIC, "IdType");
jIdTypeClass.annotate(Embeddable.class);
jIdTypeClass.field(JMod.PRIVATE, Integer.class, id1PropertyName);
jIdTypeClass.field(JMod.PRIVATE, String.class, id2PropertyName);
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.TABLE_PER_CLASS);
jBaseClass.field(JMod.PRIVATE, jIdTypeClass, compositeIdPropertyName).annotate(EmbeddedId.class);
final JDefinedClass jSubclass = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclass.annotate(Entity.class);
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> entityClass = loadClass(testFolder.getRoot(), jSubclass.name());
// WHEN
final List<String> namesOfIdProperties = EntityUtils.getNamesOfIdProperties(entityClass);
// THEN
assertThat(namesOfIdProperties.size(), equalTo(2));
assertThat(namesOfIdProperties,
hasItems(compositeIdPropertyName + "." + id1PropertyName, compositeIdPropertyName + "." + id2PropertyName));
}
@Test
public void testGetNamesOfIdPropertiesFromAClassHierarchyHavingAMethodAnnotatedWithEmbeddedId() throws Exception {
// GIVEN
final String simpleClassNameBase = "EntityClass";
final String simpleClassNameB = "SubEntityClass";
final String compositeIdPropertyName = "compositeKey";
final String id1PropertyName = "key1";
final String id2PropertyName = "key2";
final JPackage jp = jCodeModel.rootPackage();
final JDefinedClass jIdTypeClass = jp._class(JMod.PUBLIC, "IdType");
jIdTypeClass.annotate(Embeddable.class);
jIdTypeClass.field(JMod.PRIVATE, Integer.class, id1PropertyName);
jIdTypeClass.field(JMod.PRIVATE, String.class, id2PropertyName);
final JDefinedClass jBaseClass = jp._class(JMod.PUBLIC, simpleClassNameBase);
jBaseClass.annotate(Entity.class);
jBaseClass.annotate(Inheritance.class).param("strategy", InheritanceType.TABLE_PER_CLASS);
final JMethod method = jBaseClass.method(JMod.PUBLIC, jIdTypeClass, "getCompositeKey");
method.annotate(EmbeddedId.class);
method.body()._return(JExpr._null());
final JDefinedClass jSubclass = jp._class(JMod.PUBLIC, simpleClassNameB)._extends(jBaseClass);
jSubclass.annotate(Entity.class);
buildModel(testFolder.getRoot(), jCodeModel);
compileModel(testFolder.getRoot());
final Class<?> entityClass = loadClass(testFolder.getRoot(), jSubclass.name());
// WHEN
final List<String> namesOfIdProperties = EntityUtils.getNamesOfIdProperties(entityClass);
// THEN
assertThat(namesOfIdProperties.size(), equalTo(2));
assertThat(namesOfIdProperties,
hasItems(compositeIdPropertyName + "." + id1PropertyName, compositeIdPropertyName + "." + id2PropertyName));
}
protected String getEntityNameForIdGeneration(MetaClass metaClass) {
List<MetaClass> persistentAncestors = metaClass.getAncestors().stream()
.filter(mc -> tools.isPersistent(mc)) // filter out all mapped superclasses
.collect(Collectors.toList());
if (persistentAncestors.size() > 0) {
MetaClass root = persistentAncestors.get(persistentAncestors.size() - 1);
Class<?> javaClass = root.getJavaClass();
Inheritance inheritance = javaClass.getAnnotation(Inheritance.class);
if (inheritance == null || inheritance.strategy() != InheritanceType.TABLE_PER_CLASS) {
// use root of inheritance tree if the strategy is JOINED or SINGLE_TABLE because ID is stored in the root table
return root.getName();
}
}
return metaClass.getName();
}
private static boolean isSingleTable(Class<?> entity) {
Inheritance inheritance = entity.getSuperclass().getAnnotation(Inheritance.class);
return inheritance != null && inheritance.strategy() == InheritanceType.SINGLE_TABLE;
}