Enhancer.java 文件源码

private CtMethod generateFieldWriter(
        CtClass managedCtClass,
        CtField persistentField,
        AttributeTypeDescriptor typeDescriptor) {

    final FieldInfo fieldInfo = persistentField.getFieldInfo();
    final String fieldName = fieldInfo.getName();
    final String writerName = EnhancerConstants.PERSISTENT_FIELD_WRITER_PREFIX + fieldName;

    final CtMethod writer;

    try {
        if ( !enhancementContext.isLazyLoadable( persistentField ) ) {
            // not lazy-loadable...
            writer = CtNewMethod.setter( writerName, persistentField );
        }
        else {
            final String methodBody = typeDescriptor.buildWriteInterceptionBodyFragment( fieldName );
            writer = CtNewMethod.make(
                    Modifier.PRIVATE,
                    CtClass.voidType,
                    writerName,
                    new CtClass[] {persistentField.getType()},
                    null,
                    "{" + methodBody + "}",
                    managedCtClass
            );
        }

        if ( enhancementContext.doDirtyCheckingInline( managedCtClass ) && !isComposite ) {
            writer.insertBefore( typeDescriptor.buildInLineDirtyCheckingBodyFragment( persistentField ) );
        }

        if ( isComposite ) {
            StringBuilder builder = new StringBuilder();
            builder.append( " if(  " )
                    .append( EnhancerConstants.TRACKER_COMPOSITE_FIELD_NAME )
                    .append( " != null) " )
                    .append( EnhancerConstants.TRACKER_COMPOSITE_FIELD_NAME )
                    .append( ".callOwner(\"." )
                    .append( persistentField.getName() )
                    .append( "\");" );

            writer.insertBefore( builder.toString() );
        }

        //composite types
        if ( persistentField.getAnnotation( Embedded.class ) != null ) {
            //make sure to add the CompositeOwner interface
            if ( !doClassInheritCompositeOwner( managedCtClass ) ) {
                managedCtClass.addInterface( classPool.get( "org.hibernate.engine.spi.CompositeOwner" ) );
            }
            //if a composite have a embedded field we need to implement the method as well
            if ( isComposite ) {
                createTrackChangeCompositeMethod( managedCtClass );
            }


            writer.insertBefore( cleanupPreviousOwner( persistentField ) );

            writer.insertAfter( compositeMethodBody( persistentField ) );
        }

        managedCtClass.addMethod( writer );
        return writer;
    }
    catch (Exception e) {
        throw new EnhancementException(
                String.format(
                        "Could not enhance entity class [%s] to add field writer method [%s]",
                        managedCtClass.getName(),
                        writerName
                ),
                e
        );
    }
}