/*
* JBoss, Home of Professional Open Source
* Copyright 2010, Red Hat Middleware LLC, and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.hibernate.jpamodelgen;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.List;
import javax.annotation.Generated;
import javax.annotation.processing.FilerException;
import javax.lang.model.element.Element;
import javax.lang.model.element.TypeElement;
import javax.lang.model.type.DeclaredType;
import javax.lang.model.type.TypeKind;
import javax.lang.model.type.TypeMirror;
import javax.persistence.Entity;
import javax.persistence.MappedSuperclass;
import javax.tools.Diagnostic;
import javax.tools.FileObject;
import org.hibernate.jpamodelgen.model.MetaAttribute;
import org.hibernate.jpamodelgen.model.MetaEntity;
/**
* Helper class to write the actual meta model class using the {@link javax.annotation.processing.Filer} API.
*
* @author Emmanuel Bernard
* @author Hardy Ferentschik
*/
public final class ClassWriter {
private static final String META_MODEL_CLASS_NAME_SUFFIX = "_";
private ClassWriter() {
}
public static void writeFile(MetaEntity entity, Context context) {
try {
String metaModelPackage = entity.getPackageName();
StringBuffer body = generateBody( entity, context );
FileObject fo = context.getProcessingEnvironment().getFiler().createSourceFile(
getFullyQualifiedClassName( entity, metaModelPackage )
);
OutputStream os = fo.openOutputStream();
PrintWriter pw = new PrintWriter( os );
if ( !metaModelPackage.isEmpty() ) {
pw.println( "package " + metaModelPackage + ";" );
pw.println();
}
pw.println( entity.generateImports() );
pw.println( body );
pw.flush();
pw.close();
}
catch ( FilerException filerEx ) {
context.logMessage(
Diagnostic.Kind.ERROR, "Problem with Filer: " + filerEx.getMessage()
);
}
catch ( IOException ioEx ) {
context.logMessage(
Diagnostic.Kind.ERROR,
"Problem opening file to write MetaModel for " + entity.getSimpleName() + ioEx.getMessage()
);
}
}
/**
* Generate everything after import statements.
*
* @param entity The meta entity for which to write the body
* @param context The processing context
*
* @return body content
*/
private static StringBuffer generateBody(MetaEntity entity, Context context) {
StringWriter sw = new StringWriter();
PrintWriter pw = null;
try {
pw = new PrintWriter( sw );
if ( context.isAddGeneratedAnnotation() ) {
pw.println( writeGeneratedAnnotation( entity ) );
}
pw.println( writeStaticMetaModelAnnotation( entity ) );
printClassDeclaration( entity, pw, context );
pw.println();
List<MetaAttribute> members = entity.getMembers();
for ( MetaAttribute metaMember : members ) {
pw.println( " " + metaMember.getDeclarationString() );
}
pw.println();
pw.println( "}" );
return sw.getBuffer();
}
finally {
if ( pw != null ) {
pw.close();
}
}
}
private static void printClassDeclaration(MetaEntity entity, PrintWriter pw, Context context) {
pw.print( "public abstract class " + entity.getSimpleName() + META_MODEL_CLASS_NAME_SUFFIX );
final TypeMirror superClass = entity.getTypeElement().getSuperclass();
//superclass of Object is of NoType which returns some other kind
if ( superClass.getKind() == TypeKind.DECLARED ) {
//F..king Ch...t Have those people used their horrible APIs even once?
final Element superClassElement = ( (DeclaredType) superClass ).asElement();
String superClassName = ( (TypeElement) superClassElement ).getQualifiedName().toString();
if ( extendsSuperMetaModel( superClassElement, entity.isMetaComplete(), context ) ) {
pw.print( " extends " + superClassName + META_MODEL_CLASS_NAME_SUFFIX );
}
}
pw.println( " {" );
}
/**
* Checks whether this metamodel class needs to extend another metamodel class.
* This methods checks whether the processor has generated a metamodel class for the super class, but it also
* allows for the possibility that the metamodel class was generated in a previous compilation (eg it could be
* part of a separate jar. See also METAGEN-35).
*
* @param superClassElement the super class element
* @param entityMetaComplete flag indicating if the entity for which the metamodel should be generarted is metamodel
* complete. If so we cannot use reflection to decide whether we have to add the extend clause
* @param context the execution context
*
* @return {@code true} in case there is super class meta model to extend from {@code false} otherwise.
*/
private static boolean extendsSuperMetaModel(Element superClassElement, boolean entityMetaComplete, Context context) {
// if we processed the superclass in the same run we definitely need to extend
String superClassName = ( (TypeElement) superClassElement ).getQualifiedName().toString();
if ( context.containsMetaEntity( superClassName )
|| context.containsMetaEmbeddable( superClassName ) ) {
return true;
}
// to allow for the case that the metamodel class for the super entity is for example contained in another
// jar file we use reflection. However, we need to consider the fact that there is xml configuration
// and annotations should be ignored
if ( !entityMetaComplete && ( superClassElement.getAnnotation( Entity.class ) != null
|| superClassElement.getAnnotation( MappedSuperclass.class ) != null ) ) {
return true;
}
return false;
}
private static String getFullyQualifiedClassName(MetaEntity entity, String metaModelPackage) {
String fullyQualifiedClassName = "";
if ( !metaModelPackage.isEmpty() ) {
fullyQualifiedClassName = fullyQualifiedClassName + metaModelPackage + ".";
}
fullyQualifiedClassName = fullyQualifiedClassName + entity.getSimpleName() + META_MODEL_CLASS_NAME_SUFFIX;
return fullyQualifiedClassName;
}
private static String writeGeneratedAnnotation(MetaEntity entity) {
return "@" + entity.importType( Generated.class.getName() ) + "(\"JPA MetaModel for " + entity.getQualifiedName() + "\")";
}
private static String writeStaticMetaModelAnnotation(MetaEntity entity) {
return "@" + entity.importType( "javax.persistence.metamodel.StaticMetamodel" ) + "(" + entity.getSimpleName() + ".class)";
}
}