content: /*
   * Copyright (c) 2001-2008 Caucho Technology, Inc.  All rights reserved.
   *
   * The Apache Software License, Version 1.1
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. The end-user documentation included with the redistribution, if
   *    any, must include the following acknowlegement:
   *       "This product includes software developed by the
   *        Caucho Technology (http://www.caucho.com/)."
   *    Alternately, this acknowlegement may appear in the software itself,
   *    if and wherever such third-party acknowlegements normally appear.
   *
   * 4. The names "Burlap", "Resin", and "Caucho" must not be used to
   *    endorse or promote products derived from this software without prior
   *    written permission. For written permission, please contact
   *    info@caucho.com.
   *
   * 5. Products derived from this software may not be called "Resin"
   *    nor may "Resin" appear in their names without prior written
   *    permission of Caucho Technology.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL CAUCHO TECHNOLOGY OR ITS CONTRIBUTORS
   * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
   * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
   * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
   * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
   * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
   * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   *
   * @author Scott Ferguson
   */
  
  package com.caucho.hessian.io;
  
  import java.io.IOException;
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.util.logging.Level;
  import java.util.logging.Logger;
  
  /**
   * Serializing an object for known object types.
   */
  public class WriteReplaceSerializer extends AbstractSerializer
  {
    private static final Logger log
      = Logger.getLogger(WriteReplaceSerializer.class.getName());
  
    private Object _writeReplaceFactory;
    private Method _writeReplace;
    private Serializer _baseSerializer;
    
    public WriteReplaceSerializer(Class<?> cl,
                                  ClassLoader loader,
                                  Serializer baseSerializer)
    {
      introspectWriteReplace(cl, loader);
      
      _baseSerializer = baseSerializer;
    }
  
    private void introspectWriteReplace(Class<?> cl, ClassLoader loader)
    {
      try {
        String className = cl.getName() + "HessianSerializer";
  
        Class<?> serializerClass = Class.forName(className, false, loader);
  
        Object serializerObject = serializerClass.newInstance();
  
        Method writeReplace = getWriteReplace(serializerClass, cl);
  
        if (writeReplace != null) {
          _writeReplaceFactory = serializerObject;
          _writeReplace = writeReplace;
        }
      } catch (ClassNotFoundException e) {
      } catch (Exception e) {
        log.log(Level.FINER, e.toString(), e);
      }
        
      _writeReplace = getWriteReplace(cl);
      if (_writeReplace != null)
        _writeReplace.setAccessible(true);
    }
  
    /**
     * Returns the writeReplace method
     */
    protected static Method getWriteReplace(Class<?> cl, Class<?> param)
    {
      for (; cl != null; cl = cl.getSuperclass()) {
        for (Method method : cl.getDeclaredMethods()) {
          if (method.getName().equals("writeReplace")
              && method.getParameterTypes().length == 1
              && param.equals(method.getParameterTypes()[0]))
            return method;
        }
      }
  
      return null;
    }
  
    /**
     * Returns the writeReplace method
     */
    protected static Method getWriteReplace(Class<?> cl)
    {
      for (; cl != null; cl = cl.getSuperclass()) {
        Method []methods = cl.getDeclaredMethods();
        
        for (int i = 0; i < methods.length; i++) {
          Method method = methods[i];
  
          if (method.getName().equals("writeReplace") &&
              method.getParameterTypes().length == 0)
            return method;
        }
      }
  
      return null;
    }
  
    @Override
    public void writeObject(Object obj, AbstractHessianOutput out)
      throws IOException
    {
      int ref = out.getRef(obj);
      
      if (ref >= 0) {
        out.writeRef(ref);
        
        return;
      }
      
      try {
        Object repl;
  
        repl = writeReplace(obj);
  
        if (obj == repl) {
          if (log.isLoggable(Level.FINE)) { 
            log.fine(this + ": Hessian writeReplace error.  The writeReplace method (" + _writeReplace + ") must not return the same object: " + obj);
          }
          
          _baseSerializer.writeObject(obj, out);
  
          return;
        }
  
        out.writeObject(repl);
  
        out.replaceRef(repl, obj);
      } catch (RuntimeException e) {
        throw e;
      } catch (Exception e) {
        throw new RuntimeException(e);
      }
    }
    
    @Override
    protected Object writeReplace(Object obj)
    {
      try {
        if (_writeReplaceFactory != null)
          return _writeReplace.invoke(_writeReplaceFactory, obj);
        else
          return _writeReplace.invoke(obj);
      } catch (RuntimeException e) {
        throw e;
      } catch (InvocationTargetException e) {
        throw new RuntimeException(e.getCause());
      } catch (Exception e) {
        throw new RuntimeException(e);
      }
    }
  }
  