/*****************************************************************
** DemoPassByReference - demonstrate passing variables vs object
**                       variables to methods
**
** This program generates the following output:
**
**    25
**    Java is fun!
**    Hello, world
**    -----------------
**    9
**    fun
**    Hello, Java world
**    -----------------
**    25
**    Java is fun!
**    Hello, Java world
**
** (c) Scott MacKenzie, 2000                             
******************************************************************/
public class DemoPassByReference
{
   public static void main(String[] args)
   {
      // declare and initialize variables and objects
      int i = 25;
      String s = "Java is fun!";
      StringBuffer sb = new StringBuffer("Hello, world");

      // print variable i and objects s and sb
      System.out.println(i);                            // print it (1)
      System.out.println(s);                            // print it (2)
      System.out.println(sb);                           // print it (3)
      System.out.println("-----------------");

      // attempt to change i, s, and sb using methods
      iMethod(i);
      sMethod(s);
      sbMethod(sb);
      System.out.println("-----------------");

      // print variable i and objects s and sb (again)
      System.out.println(i);                            // print it (7)
      System.out.println(s);                            // print it (8)
      System.out.println(sb);                           // print it (9)
   }

   public static void iMethod(int iTest)
   {
      iTest = 9;                                        // change it
      System.out.println(iTest);                        // print it (4)
      return;
   }

   public static void sMethod(String sTest)
   {
      sTest = sTest.substring(8, 11);                   // change it
      System.out.println(sTest);                        // print it (5)
      return;
   }

   public static void sbMethod(StringBuffer sbTest)
   {
      sbTest = sbTest.insert(7, "Java ");               // change it
      System.out.println(sbTest);                       // print it (6)
      return;
   }
}