/*
 *  File: TestEquals.java
 *  Author: Java, Java, Java
 *  Description: This program illustrates the differences
 *   between the == operator and the equals() method as
 *   applied to objects in general.  The == operator implements
 *   object identity, where two object references are identical if
 *   they refer to the same object. The default implementation of
 *   Object.equals() just implements object identity. The default
 *   equals() method should be overridden to define equality in
 *   a way that is appropriate to a given subclass of Object.
 */

import javax.swing.*;

public class TestEquals {
    static JButton b1 = new JButton ("a");
    static JButton b2 = new JButton ("b");
    static JButton b3 = b2;

    private static void isEqual(Object o1, Object o2) {
        if (o1.equals(o2))
            System.out.println(o1.toString() + " equals " + o2.toString());
        else
            System.out.println(o1.toString() + " does NOT equal " + o2.toString());
    } // isEqual()

    private static void isIdentical( Object o1, Object o2 ) {
        if (o1 == o2)
            System.out.println(o1.toString() + " is identical to " + o2.toString());
        else
            System.out.println(o1.toString() + " is NOT identical to " + o2.toString());
    } // isIdentical()

    public static void main(String argv[]) {
        isEqual(b1, b2);         // not equal
        isEqual(b1, b3);         // not equal
        isEqual(b2, b3);         // equal

        isIdentical(b1, b2);     // not identical
        isIdentical(b1, b3);     // not identical
        isIdentical(b2, b3);     // identical
    } // main()
} // TestEquals