/* * class: SerializationPacking -- Store an object as serialized data * * Copyright (C) 1997 Pharos IP Pty Ltd * $Id: SerializationPacking.java,v 1.4 1997-10-29 17:11:20+10 mbp Exp $ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ package au.com.pharos.packing; import java.io.ByteArrayOutputStream; import java.io.ObjectOutputStream; import java.io.ByteArrayInputStream; import java.io.ObjectInputStream; import java.io.IOException; /** A packing strategy which stores and retrieves objects using * Java serialization. * * @version $Revision: 1.4 $ * @author Martin Pool * @see au.com.pharos.packing.Packing **/ public class SerializationPacking extends Packing implements java.io.Serializable { /** Convert an object to a Java serialization format. * * @returns a buffer containing a a serialized representation of obj; * or null if obj if null * @exception IllegalArgumentException if obj (or any object * referred to by obj) cannot be serialized **/ public byte[] toBytes(Object obj) throws IllegalArgumentException { if (obj == null) return null; // Serialize via a stream into a buffer ByteArrayOutputStream byteStream = new ByteArrayOutputStream(); try { ObjectOutputStream objStream = new ObjectOutputStream(byteStream); objStream.writeObject(obj); // Don't close the stream, or you will lose the byte array objStream.flush(); } catch (IOException e) { throw new IllegalArgumentException("IOException during serialization: " + e.toString()); } return byteStream.toByteArray(); } /** Interprets raw as a Java serialization stream, and * returns the first object read from that stream. * *
Note:There is currently no means by which any later * objects in the can be retrieved: it is assumed that the object * written to the buffer contains references to all the * information required. This is consistent with the fact that * toBytes() stores only a single object, so this packing strategy * is completely reversable. **/ // FIXME: Is the correct word 'reversable', 'reflexive', or // something else? -- mbp@pharos.com.au public Object fromBytes(byte[] raw) { if (raw == null) return null; Object obj; try { ByteArrayInputStream byteStream = new ByteArrayInputStream(raw); ObjectInputStream objStream = new ObjectInputStream(byteStream); obj = objStream.readObject(); objStream.close(); } catch (IOException e) { throw new IllegalArgumentException("Exception during deserialization: " + e.toString()); } catch (ClassNotFoundException e) { throw new IllegalArgumentException("Exception during deserialization: " + e.toString()); } return obj; } }