package org.apache.jcs.utils.serialization;
/*
* 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.
*/
import java.io.IOException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.jcs.engine.CacheElement;
import org.apache.jcs.engine.CacheElementSerialized;
import org.apache.jcs.engine.behavior.ICacheElement;
import org.apache.jcs.engine.behavior.ICacheElementSerialized;
import org.apache.jcs.engine.behavior.IElementSerializer;
/**
* This uses a supplied Serialer to convert to and from cache elements.
* <p>
* @author Aaron Smuts
*/
public class SerializationConversionUtil
{
private final static Log log = LogFactory.getLog( SerializationConversionUtil.class );
/**
* This returns a wrapper that has a serialized version of the value instead
* of the value.
* <p>
* @param element
* @param elementSerializer
* the serializer to be used.
* @return null for null;
* @throws IOException
*/
public static ICacheElementSerialized getSerializedCacheElement( ICacheElement element,
IElementSerializer elementSerializer )
throws IOException
{
if ( element == null )
{
return null;
}
byte[] serialzedValue = null;
// if it has already been serialized, don't do it again.
if ( element instanceof ICacheElementSerialized )
{
serialzedValue = ( (ICacheElementSerialized) element ).getSerializedValue();
}
else
{
if ( elementSerializer != null )
{
try
{
serialzedValue = elementSerializer.serialize( element.getVal() );
}
catch ( IOException e )
{
log.error( "Problem serializing object.", e );
throw e;
}
}
else
{
// we could just use the default.
log.warn( "ElementSerializer is null. Could not serialize object." );
throw new IOException( "Could not serialize object. The ElementSerializer is null." );
}
}
ICacheElementSerialized serialized = new CacheElementSerialized( element.getCacheName(), element.getKey(),
serialzedValue, element.getElementAttributes() );
return serialized;
}
/**
* This returns a wrapper that has a de-serialized version of the value
* instead of the serialized value.
* <p>
* @param serialized
* @param elementSerializer
* the serializer to be used.
* @return null for null;
* @throws IOException
* @throws ClassNotFoundException
*/
public static ICacheElement getDeSerializedCacheElement( ICacheElementSerialized serialized,
IElementSerializer elementSerializer )
throws IOException, ClassNotFoundException
{
if ( serialized == null )
{
return null;
}
Object deSerialzedValue = null;
if ( elementSerializer != null )
{
try
{
try
{
deSerialzedValue = elementSerializer.deSerialize( serialized.getSerializedValue() );
}
catch ( ClassNotFoundException e )
{
log.error( "Problem de-serializing object.", e );
throw e;
}
}
catch ( IOException e )
{
log.error( "Problem de-serializing object.", e );
throw e;
}
}
else
{
// we could just use the default.
log.warn( "ElementSerializer is null. Could not serialize object." );
}
ICacheElement deSerialized = new CacheElement( serialized.getCacheName(), serialized.getKey(), deSerialzedValue );
deSerialized.setElementAttributes( serialized.getElementAttributes() );
return deSerialized;
}
}