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/*
* Copyright 2002-2004 The Apache Software Foundation.
*
* Licensed 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.lang;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.io.Serializable;
/**
* <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:nissim@nksystems.com">Nissim Karpenstein</a>
* @author <a href="mailto:janekdb@yahoo.co.uk">Janek Bogucki</a>
* @author <a href="mailto:dlr@finemaltcoding.com">Daniel Rall</a>
* @author Stephen Colebourne
* @author Jeff Varszegi
* @author Gary Gregory
* @since 1.0
* @version $Id: SerializationUtils.java,v 1.13 2004/02/18 22:59:50 ggregory Exp $
*/
public class SerializationUtils {
/**
* <p>SerializationUtils instances should NOT be constructed in standard programming.
* Instead, the class should be used as <code>SerializationUtils.clone(object)</code>.</p>
*
* <p>This constructor is public to permit tools that require a JavaBean instance
* to operate.</p>
* @since 2.0
*/
public SerializationUtils() {
super();
}
// 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) {
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) {
if (outputStream == null) {
throw new IllegalArgumentException("The OutputStream must not be null");
}
ObjectOutputStream out = null;
try {
// stream closed in the finally
out = new ObjectOutputStream(outputStream);
out.writeObject(obj);
} catch (IOException ex) {
throw new SerializationException(ex);
} finally {
try {
if (out != null) {
out.close();
}
} catch (IOException ex) {
// ignore;
}
}
}
/**
* <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) {
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) {
if (inputStream == null) {
throw new IllegalArgumentException("The InputStream must not be null");
}
ObjectInputStream in = null;
try {
// stream closed in the finally
in = new ObjectInputStream(inputStream);
return in.readObject();
} catch (ClassNotFoundException ex) {
throw new SerializationException(ex);
} catch (IOException ex) {
throw new SerializationException(ex);
} finally {
try {
if (in != null) {
in.close();
}
} catch (IOException ex) {
// ignore
}
}
}
/**
* <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) {
if (objectData == null) {
throw new IllegalArgumentException("The byte[] must not be null");
}
ByteArrayInputStream bais = new ByteArrayInputStream(objectData);
return deserialize(bais);
}
}
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