001package org.apache.commons.jcs.utils.serialization; 002 003/* 004 * Licensed to the Apache Software Foundation (ASF) under one 005 * or more contributor license agreements. See the NOTICE file 006 * distributed with this work for additional information 007 * regarding copyright ownership. The ASF licenses this file 008 * to you under the Apache License, Version 2.0 (the 009 * "License"); you may not use this file except in compliance 010 * with the License. You may obtain a copy of the License at 011 * 012 * http://www.apache.org/licenses/LICENSE-2.0 013 * 014 * Unless required by applicable law or agreed to in writing, 015 * software distributed under the License is distributed on an 016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 017 * KIND, either express or implied. See the License for the 018 * specific language governing permissions and limitations 019 * under the License. 020 */ 021 022import org.apache.commons.jcs.engine.behavior.IElementSerializer; 023import org.apache.commons.jcs.io.ObjectInputStreamClassLoaderAware; 024import org.apache.commons.jcs.utils.zip.CompressionUtil; 025 026import java.io.BufferedInputStream; 027import java.io.ByteArrayInputStream; 028import java.io.ByteArrayOutputStream; 029import java.io.IOException; 030import java.io.ObjectInputStream; 031import java.io.ObjectOutputStream; 032 033/** 034 * Performs default serialization and de-serialization. It gzips the value. 035 */ 036public class CompressingSerializer 037 implements IElementSerializer 038{ 039 /** 040 * Serializes an object using default serialization. Compresses the byte array. 041 * <p> 042 * @param obj object 043 * @return byte[] 044 * @throws IOException on i/o problem 045 */ 046 @Override 047 public <T> byte[] serialize( T obj ) 048 throws IOException 049 { 050 byte[] uncompressed = serializeObject( obj ); 051 byte[] compressed = CompressionUtil.compressByteArray( uncompressed ); 052 return compressed; 053 } 054 055 /** 056 * Does the basic serialization. 057 * <p> 058 * @param obj object 059 * @return byte[] 060 * @throws IOException on i/o problem 061 */ 062 protected <T> byte[] serializeObject( T obj ) 063 throws IOException 064 { 065 ByteArrayOutputStream baos = new ByteArrayOutputStream(); 066 ObjectOutputStream oos = new ObjectOutputStream( baos ); 067 try 068 { 069 oos.writeObject( obj ); 070 } 071 finally 072 { 073 oos.close(); 074 } 075 byte[] uncompressed = baos.toByteArray(); 076 return uncompressed; 077 } 078 079 /** 080 * Uses default de-serialization to turn a byte array into an object. Decompresses the value 081 * first. All exceptions are converted into IOExceptions. 082 * <p> 083 * @param data bytes of data 084 * @return Object 085 * @throws IOException on i/o problem 086 * @throws ClassNotFoundException if class is not found during deserialization 087 */ 088 @Override 089 public <T> T deSerialize( byte[] data, ClassLoader loader ) 090 throws IOException, ClassNotFoundException 091 { 092 if ( data == null ) 093 { 094 return null; 095 } 096 byte[] decompressedByteArray = CompressionUtil.decompressByteArray( data ); 097 return deserializeObject( decompressedByteArray ); 098 } 099 100 /** 101 * Does the standard deserialization. 102 * <p> 103 * @param decompressedByteArray array of decompressed bytes 104 * @return Object 105 * @throws IOException on i/o error 106 * @throws ClassNotFoundException if class is not found during deserialization 107 */ 108 protected <T> T deserializeObject( byte[] decompressedByteArray ) 109 throws IOException, ClassNotFoundException 110 { 111 ByteArrayInputStream bais = new ByteArrayInputStream( decompressedByteArray ); 112 BufferedInputStream bis = new BufferedInputStream( bais ); 113 ObjectInputStream ois = new ObjectInputStreamClassLoaderAware( bis, null ); 114 115 try 116 { 117 @SuppressWarnings("unchecked") // Need to cast from Object 118 T readObject = (T) ois.readObject(); 119 return readObject; 120 } 121 finally 122 { 123 ois.close(); 124 } 125 } 126}