/* * Copyright (c) 2000 David Flanagan.  All rights reserved. * This code is from the book Java Examples in a Nutshell, 2nd Edition. * It is provided AS-IS, WITHOUT ANY WARRANTY either expressed or implied. * You may study, use, and modify it for any non-commercial purpose. * You may distribute it non-commercially as long as you retain this notice. * For a commercial use license, or to purchase the book (recommended), * visit http://www.davidflanagan.com/javaexamples2. */package com.davidflanagan.examples.serialization;import java.io.*;/** * A simple class that implements a growable array of ints, and knows * how to serialize itself as efficiently as a non-growable array. **/public class IntList implements Serializable {    protected int[] data = new int[8]; // An array to store the numbers.    protected transient int size = 0;  // Index of next unused element of array        /** Return an element of the array */    public int get(int index) throws ArrayIndexOutOfBoundsException {        if (index >= size) throw new ArrayIndexOutOfBoundsException(index);        else return data[index];    }        /** Add an int to the array, growing the array if necessary */    public void add(int x) {        if (data.length==size) resize(data.length*2);  // Grow array if needed.        data[size++] = x;                              // Store the int in it.    }        /** An internal method to change the allocated size of the array */    protected void resize(int newsize) {	int[] newdata = new int[newsize];            // Create a new array        System.arraycopy(data, 0, newdata, 0, size); // Copy array elements.	data = newdata;                              // Replace old array    }        /** Get rid of unused array elements before serializing the array */    private void writeObject(ObjectOutputStream out) throws IOException {        if (data.length > size) resize(size);  // Compact the array.        out.defaultWriteObject();              // Then write it out normally.    }        /** Compute the transient size field after deserializing the array */    private void readObject(ObjectInputStream in)	throws IOException, ClassNotFoundException    {        in.defaultReadObject();                // Read the array normally.        size = data.length;                    // Restore the transient field.    }    /**     * Does this object contain the same values as the object o?     * We override this Object method so we can test the class.     **/    public boolean equals(Object o) {	if (!(o instanceof IntList)) return false;	IntList that = (IntList) o;	if (this.size != that.size) return false;	for(int i = 0; i < this.size; i++)	    if (this.data[i] != that.data[i]) return false;	return true;    }    /** A main() method to prove that it works */    public static void main(String[] args) throws Exception {	IntList list = new IntList();	for(int i = 0; i < 100; i++) list.add((int)(Math.random()*40000));	IntList copy = (IntList)Serializer.deepclone(list);	if (list.equals(copy)) System.out.println("equal copies");	Serializer.store(list, new File("intlist.ser"));    }}