/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2002-2003 The Apache Software Foundation. All rights
* reserved.
*
* 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 acknowledgement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact [email protected].
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Software Foundation.
*
* 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 THE APACHE SOFTWARE FOUNDATION 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.hibernate.util;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.io.Serializable;
import java.io.ObjectStreamClass;
import java.io.ObjectInputStream;
import org.hibernate.type.SerializationException;
import org.hibernate.Hibernate;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* <p>Assists with the serialization process and performs additional functionality based
* on serialization.</p>
* <p>
* <ul>
* <li>Deep clone using serialization
* <li>Serialize managing finally and IOException
* <li>Deserialize managing finally and IOException
* </ul>
*
* <p>This class throws exceptions for invalid <code>null</code> inputs.
* Each method documents its behaviour in more detail.</p>
*
* @author <a href="mailto:[email protected]">Nissim Karpenstein</a>
* @author <a href="mailto:[email protected]">Janek Bogucki</a>
* @author <a href="mailto:[email protected]">Daniel Rall</a>
* @author Stephen Colebourne
* @author Jeff Varszegi
* @author Gary Gregory
* @since 1.0
* @version $Id: SerializationHelper.java 9180 2006-01-30 23:51:27Z steveebersole $
*/
public final class SerializationHelper {
private static final Log log = LogFactory.getLog(SerializationHelper.class);
private SerializationHelper() {}
// Clone
//-----------------------------------------------------------------------
/**
* <p>Deep clone an <code>Object</code> using serialization.</p>
*
* <p>This is many times slower than writing clone methods by hand
* on all objects in your object graph. However, for complex object
* graphs, or for those that don't support deep cloning this can
* be a simple alternative implementation. Of course all the objects
* must be <code>Serializable</code>.</p>
*
* @param object the <code>Serializable</code> object to clone
* @return the cloned object
* @throws SerializationException (runtime) if the serialization fails
*/
public static Object clone(Serializable object) throws SerializationException {
log.trace("Starting clone through serialization");
return deserialize( serialize(object) );
}
// Serialize
//-----------------------------------------------------------------------
/**
* <p>Serializes an <code>Object</code> to the specified stream.</p>
*
* <p>The stream will be closed once the object is written.
* This avoids the need for a finally clause, and maybe also exception
* handling, in the application code.</p>
*
* <p>The stream passed in is not buffered internally within this method.
* This is the responsibility of your application if desired.</p>
*
* @param obj the object to serialize to bytes, may be null
* @param outputStream the stream to write to, must not be null
* @throws IllegalArgumentException if <code>outputStream</code> is <code>null</code>
* @throws SerializationException (runtime) if the serialization fails
*/
public static void serialize(Serializable obj, OutputStream outputStream) throws SerializationException {
if (outputStream == null) {
throw new IllegalArgumentException("The OutputStream must not be null");
}
if ( log.isTraceEnabled() ) {
if ( Hibernate.isInitialized( obj ) ) {
log.trace( "Starting serialization of object [" + obj + "]" );
}
else {
log.trace( "Starting serialization of [uninitialized proxy]" );
}
}
ObjectOutputStream out = null;
try {
// stream closed in the finally
out = new ObjectOutputStream(outputStream);
out.writeObject(obj);
}
catch (IOException ex) {
throw new SerializationException("could not serialize", ex);
}
finally {
try {
if (out != null) out.close();
}
catch (IOException ignored) {}
}
}
/**
* <p>Serializes an <code>Object</code> to a byte array for
* storage/serialization.</p>
*
* @param obj the object to serialize to bytes
* @return a byte[] with the converted Serializable
* @throws SerializationException (runtime) if the serialization fails
*/
public static byte[] serialize(Serializable obj) throws SerializationException {
ByteArrayOutputStream baos = new ByteArrayOutputStream(512);
serialize(obj, baos);
return baos.toByteArray();
}
// Deserialize
//-----------------------------------------------------------------------
/**
* <p>Deserializes an <code>Object</code> from the specified stream.</p>
*
* <p>The stream will be closed once the object is written. This
* avoids the need for a finally clause, and maybe also exception
* handling, in the application code.</p>
*
* <p>The stream passed in is not buffered internally within this method.
* This is the responsibility of your application if desired.</p>
*
* @param inputStream the serialized object input stream, must not be null
* @return the deserialized object
* @throws IllegalArgumentException if <code>inputStream</code> is <code>null</code>
* @throws SerializationException (runtime) if the serialization fails
*/
public static Object deserialize(InputStream inputStream) throws SerializationException {
if (inputStream == null) {
throw new IllegalArgumentException("The InputStream must not be null");
}
log.trace("Starting deserialization of object");
CustomObjectInputStream in = null;
try {
// stream closed in the finally
in = new CustomObjectInputStream(inputStream);
return in.readObject();
}
catch (ClassNotFoundException ex) {
throw new SerializationException("could not deserialize", ex);
}
catch (IOException ex) {
throw new SerializationException("could not deserialize", ex);
}
finally {
try {
if (in != null) in.close();
}
catch (IOException ex) {}
}
}
/**
* <p>Deserializes a single <code>Object</code> from an array of bytes.</p>
*
* @param objectData the serialized object, must not be null
* @return the deserialized object
* @throws IllegalArgumentException if <code>objectData</code> is <code>null</code>
* @throws SerializationException (runtime) if the serialization fails
*/
public static Object deserialize(byte[] objectData) throws SerializationException {
if (objectData == null) {
throw new IllegalArgumentException("The byte[] must not be null");
}
ByteArrayInputStream bais = new ByteArrayInputStream(objectData);
return deserialize(bais);
}
/**
* Custom ObjectInputStream implementation to more appropriately handle classloading
* within app servers (mainly jboss - hence this class inspired by jboss's class of
* the same purpose).
*/
private static final class CustomObjectInputStream extends ObjectInputStream {
public CustomObjectInputStream(InputStream in) throws IOException {
super(in);
}
protected Class resolveClass(ObjectStreamClass v) throws IOException, ClassNotFoundException {
String className = v.getName();
Class resolvedClass = null;
log.trace("Attempting to locate class [" + className + "]");
ClassLoader loader = Thread.currentThread().getContextClassLoader();
try {
resolvedClass = loader.loadClass(className);
log.trace("Class resolved through context class loader");
}
catch(ClassNotFoundException e) {
log.trace("Asking super to resolve");
resolvedClass = super.resolveClass(v);
}
return resolvedClass;
}
}
}
|