/*

  * Licensed to the Apache Software Foundation (ASF) under one or more

  * contributor license agreements.  See the NOTICE file distributed with

  * this work for additional information regarding copyright ownership.

  * The ASF licenses this file to You 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.apache.commons.javaflow.bytecode.transformation.asm;

 import java.io.IOException;

 import java.io.InputStream;

 import org.apache.commons.javaflow.bytecode.transformation.ResourceTransformer;

 import org.objectweb.asm.ClassReader;

 import org.objectweb.asm.ClassWriter;

 import org.objectweb.asm.util.CheckClassAdapter;

 /**

  * AsmClassTransformer

  * 

  * @author Eugene Kuleshov

  */

 public final class AsmClassTransformer implements ResourceTransformer {

     public byte[] transform(InputStream is) throws IOException {

         return transform(new ClassReader(is));

     }

     public byte[] transform(final byte[] original) {

         return transform(new ClassReader(original));

     }

     private byte[] transform(ClassReader cr) {

         // final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS);

         final ClassWriter cw = new ClassWriter(true, false);

         // print bytecode before transformation

         // cr.accept(new TraceClassVisitor(new ContinuationClassAdapter(this, cw), new PrintWriter(System.out)), false);

         // prints bytecode after transformation

         // cr.accept(new ContinuationClassAdapter(this, new TraceClassVisitor(cw, new PrintWriter(System.err))), 0);

         // cr.accept(new ContinuationClassAdapter(this, new TraceClassVisitor(cw, new PrintWriter(System.err))), false);

         cr.accept(new ContinuationClassAdapter(new CheckClassAdapter(cw)), false);

         byte[] bytecode = cw.toByteArray();

         // CheckClassAdapter.verify(new ClassReader(bytecode), true);

         // new ClassReader(bytecode).accept(new ASMifierClassVisitor(new PrintWriter(System.err)), false);

         // ClassWriter cww = new ClassWriter(ClassWriter.COMPUTE_FRAMES);

         // new ClassReader(bytecode).accept(cww, ClassReader.SKIP_DEBUG);

         // new ClassReader(cww.toByteArray()).accept(new TraceClassVisitor(new PrintWriter(System.err)), 0);

         return bytecode;

     }

 }