/* * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved. * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * -Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * -Redistribution in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * Neither the name of Oracle nor the names of * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * This software is provided "AS IS," without a warranty of any * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY * EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY * DAMAGES OR LIABILITIES SUFFERED BY LICENSEE AS A RESULT OF OR * RELATING TO USE, MODIFICATION OR DISTRIBUTION OF THE SOFTWARE OR * ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE * FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, * SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF * THE USE OF OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS BEEN * ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that Software is not designed, licensed or * intended for use in the design, construction, operation or * maintenance of any nuclear facility. */ import java.io.*; /** * When using the Externalizable Interface, an externalizable object * must implement a writeExternal method to save the state of the object. * It must also explicitly coordinate with its supertype to save its state. * This simple example shows how to do this for an object whose supertype * is also externalizable. * * How to Run: * Compile the file: javac Savesuper.java * Then run: java Savesuper.java * * This should print out a book object before and after serialization. * * Tested and compiled on JDK 1.1 & the Java 2 SDK, v1.2 */ public class Savesuper { /** * Create an Book (subclass of reading material) object, serialize it, * deserialize it and see that they are the same. So, basically test that * this Externalizable example's works */ public static void main(String args[]) { // create a Book object Book bookorg = new Book(100, "How to Serialize", true, "R.R", "Serialization", 97); Book booknew = null; //serialize the book try { FileOutputStream fo = new FileOutputStream("tmp"); ObjectOutputStream so = new ObjectOutputStream(fo); so.writeObject(bookorg); so.flush(); } catch (Exception e) { System.out.println(e); System.exit(1); } // de-serialize the Book try { FileInputStream fi = new FileInputStream("tmp"); ObjectInputStream si = new ObjectInputStream(fi); booknew = (Book) si.readObject(); } catch (Exception e) { System.out.println(e); System.exit(1); } /* * Print out the original and new book information * It should be the same if we did everything correctly! */ System.out.println(); System.out.println("Printing original book..."); System.out.println(bookorg); System.out.println("Printing new book... "); System.out.println(booknew); System.out.println("Both original and new should be the same!"); System.out.println(); } }