/*

  * 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.stores;

 import java.util.ArrayList;

 import java.util.Collection;

 import java.util.Iterator;

 import org.apache.bcel.Repository;

 import org.apache.bcel.util.ClassLoaderRepository;

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

 import org.apache.commons.javaflow.bytecode.transformation.bcel.BcelClassTransformer;

 import org.apache.commons.jci.stores.MemoryResourceStore;

 import org.apache.commons.jci.stores.ResourceStore;

 import org.apache.commons.jci.stores.TransactionalResourceStore;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 /**

  * Due to the BCEL dependency handling all

  * classes have to be store first and then

  * be rewritten. Otherwise we could just

  * delegate to the TransformingResourceStore

  * 

  * @author tcurdt

  */

 public final class JavaflowResourceStore extends TransactionalResourceStore {

     private final static Log log = LogFactory.getLog(JavaflowResourceStore.class);

     private final TransformingResourceStore tstore;

     private final Collection changes = new ArrayList();

     public JavaflowResourceStore() {

         this(new MemoryResourceStore());

     }

     public JavaflowResourceStore(final ResourceStore pStore) {

         super(pStore);

         tstore = new TransformingResourceStore(

                 pStore,

                 new ResourceTransformer[] { new BcelClassTransformer() }

                 );

         Repository.setRepository(new ClassLoaderRepository(this.getClass().getClassLoader()));

     }

     public void write(final String pResourceName, final byte[] pResourceData) {

         super.write(pResourceName, pResourceData);

         changes.add(pResourceName);

     }

     public void onStart() {

         changes.clear();

     }

     public void onStop() {

         if (changes.size() > 0) {

             log.debug("rewriting"  + changes);

             for (Iterator it = changes.iterator(); it.hasNext();) {

                 final String clazzName = (String) it.next();

                 try {

                     final byte[] oldClazz = super.read(clazzName);

                     if (oldClazz == null) {

                         throw new ClassNotFoundException("could not find " + clazzName);

                     }

                     tstore.write(clazzName, oldClazz);

                     log.debug("rewrote " + clazzName);

                 } catch (ClassNotFoundException e) {

                     log.error("", e);

                 }

             }

             changes.clear();

         }

     }

 }