001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.wicket.serialize.java;
018
019import java.io.IOException;
020import java.io.InputStream;
021import java.io.ObjectInputStream;
022import java.io.ObjectOutputStream;
023import java.io.OutputStream;
024import java.util.zip.Deflater;
025import java.util.zip.DeflaterOutputStream;
026import java.util.zip.Inflater;
027import java.util.zip.InflaterInputStream;
028
029/**
030 * A {@link JavaSerializer} that deflates the outputstream on the fly, reducing page store size by
031 * up to a factor 8. Be advised that deflating serialized objects comes at a price of about 2-20ms
032 * per page request, depending on the size of the page and the cpu power of the machine.
033 * 
034 * <p>
035 * To use this serializer, put the following code in your application's init:
036 * 
037 * <pre>
038 * getFrameworkSettings().setSerializer(new DeflatedJavaSerializer(getApplicationKey()));
039 * </pre>
040 * 
041 * @author papegaaij
042 */
043public class DeflatedJavaSerializer extends JavaSerializer
044{
045        private static final int COMPRESS_BUF_SIZE = 4 * 1024;
046
047        /**
048         * Construct.
049         * 
050         * @param applicationKey
051         */
052        public DeflatedJavaSerializer(String applicationKey)
053        {
054                super(applicationKey);
055        }
056
057        @Override
058        protected ObjectOutputStream newObjectOutputStream(OutputStream out) throws IOException
059        {
060                return super.newObjectOutputStream(new DeflaterOutputStream(out, createDeflater(),
061                        COMPRESS_BUF_SIZE));
062        }
063
064        /**
065         * Creates the {@code Deflater}. Override this method to customize the deflater, for example to
066         * change the compression level and/or strategy.
067         * 
068         * @return the {@code Deflater}
069         */
070        protected Deflater createDeflater()
071        {
072                return new Deflater(Deflater.BEST_SPEED);
073        }
074
075        @Override
076        protected ObjectInputStream newObjectInputStream(InputStream in) throws IOException
077        {
078                return super.newObjectInputStream(new InflaterInputStream(in, new Inflater(),
079                        COMPRESS_BUF_SIZE));
080        }
081}