Java Inheritance类代码示例

import javax.persistence.Inheritance; //导入依赖的package包/类
/**
 * Determine the inheritance type and discriminator properties.
 */
private void buildInheritance() {
	// Check, if we've got an explicit inheritance type
	final Inheritance inheritance = this.entityClass.getAnnotation(Inheritance.class);
	if (inheritance != null) {
		this.inheritanceType = inheritance.strategy();
	}

	// Find the root of our hierarchy
	this.hierarchyRoot = this;
	findHierarchyRoot(this.entityClass.getSuperclass());

	// We scan only classes that we are about to write
	// So we don't know, that there is a subclass entity - until we find one
	// This could be to late for InheritanceType.SINGLE_TABLE - the defaault type
	// That's why we build a discriminator, if one of the inheritance annotations exists
	if (this.inheritanceType == null && this.entityClass.isAnnotationPresent(DiscriminatorColumn.class)
			|| this.entityClass.isAnnotationPresent(DiscriminatorValue.class)) {
		this.inheritanceType = InheritanceType.SINGLE_TABLE;
	}

	buildDiscriminator();
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
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() );
	}
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
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;
	}
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
@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));
}
 

import javax.persistence.Inheritance; //导入依赖的package包/类
protected String getEntityNameForIdGeneration(MetaClass metaClass) {
    MetaClass result = metaClass.getAncestors().stream()
            .filter(mc -> {
                // use root of inheritance tree if the strategy is JOINED because ID is stored in the root table
                Class<?> javaClass = mc.getJavaClass();
                Inheritance inheritance = javaClass.getAnnotation(Inheritance.class);
                return inheritance != null && inheritance.strategy() == InheritanceType.JOINED;
            })
            .findFirst()
            .orElse(metaClass);
    return result.getName();
}