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123     Bob     100
456     Jill    900
123     Bob     100

Review of ==

The == (equal-equal) operator is an alias detector. It checks if two reference variables refer to the same object. It does not actually look at the objects. The following program segment illustrates this:

    CheckingAccount account1 = new CheckingAccount( "123", "Bob", 100 );
    CheckingAccount account2 = new CheckingAccount( "456", "Jill", 900 );
    CheckingAccount account3; 
    account3 = account1;
    if ( account1 == account 3 )
       System.out.println("An alias has been detected!");
       System.out.println("These are different objects!");

It will print out An alias has been detected!.


Say that the following lines are added to the program (immediately following the lines already there):

    account3.processCheck( 85 );  // subtract 100 cents, including service charge

What will be printed?