001    /****************************************************************
002     * Licensed to the Apache Software Foundation (ASF) under one   *
003     * or more contributor license agreements.  See the NOTICE file *
004     * distributed with this work for additional information        *
005     * regarding copyright ownership.  The ASF licenses this file   *
006     * to you under the Apache License, Version 2.0 (the            *
007     * "License"); you may not use this file except in compliance   *
008     * with the License.  You may obtain a copy of the License at   *
009     *                                                              *
010     *   http://www.apache.org/licenses/LICENSE-2.0                 *
011     *                                                              *
012     * Unless required by applicable law or agreed to in writing,   *
013     * software distributed under the License is distributed on an  *
014     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
015     * KIND, either express or implied.  See the License for the    *
016     * specific language governing permissions and limitations      *
017     * under the License.                                           *
018     ****************************************************************/
019    
020    package org.apache.james.repository.file;
021    
022    import java.io.IOException;
023    import java.io.InputStream;
024    import java.io.ObjectInputStream;
025    import java.io.ObjectStreamClass;
026    import java.io.StreamCorruptedException;
027    
028    /**
029     * A special ObjectInputStream to handle highly transient classes hosted by
030     * Avalon components that are juggling many classloaders.
031     */
032    public class ClassLoaderObjectInputStream extends ObjectInputStream {
033        private ClassLoader m_classLoader;
034    
035        public ClassLoaderObjectInputStream(final ClassLoader classLoader, final InputStream inputStream) throws IOException, StreamCorruptedException {
036            super(inputStream);
037            m_classLoader = classLoader;
038        }
039    
040        protected Class resolveClass(final ObjectStreamClass objectStreamClass) throws IOException, ClassNotFoundException {
041            final Class clazz = Class.forName(objectStreamClass.getName(), false, m_classLoader);
042    
043            if (null != clazz) {
044                return clazz; // the classloader knows of the class
045            } else {
046                // classloader knows not of class, let the super classloader do it
047                return super.resolveClass(objectStreamClass);
048            }
049        }
050    }