First  value of the result: 0
Second value of the result: 14

Object References as Parameters

Object references can be parameters. This works the same way as with primitive data: call by value is used, but now the value is a reference to an object. Since the invoked method has a reference to an object, it can use that object the same as any method. Here is an example program:

class ObjectPrinter
{
  public void print( String st )
  {
    System.out.println("Value of parameter: " + st );    
  }
}

class OPTester
{
  public static void main ( String[] args )
  {
    String message = "Only One Object" ;

    ObjectPrinter op = new ObjectPrinter();

    System.out.println("First  value of message: " + message );    
    op.print( message );
    System.out.println("Second value of message: " + message );    
  }
}

First  value of message: 
Value of parameter: 
Second value of message: