JPAOverriddenAnnotationReader.java 文件源码

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;
    }
}