Program to Demonstrate Call by Value and Call by Reference in Java (BlueJ)

/***** PROGRAM TO DEMONSTRATE CALL BY REFERENCE *****/
public class CallByRef
{
   public static  int num1 = 100, num2 = 200;
    public static void main()
    {
         CallByRef cbr = new CallByRef();
        
        System.out.println(“***** Program to demonstrate call by reference *****”);
        System.out.println(“Value of num1 before call to swap :”+cbr.num1);
        System.out.println(“Value of num2 before call to swap :”+cbr.num2);
        System.out.println(“***********************************************”);
      
        swap(cbr); // calling swap method by reference
       
        System.out.println(“Value of num1 after call to swap :”+cbr.num1);
        System.out.println(“Value of num2 after call to swap :”+cbr.num2);
        System.out.println(“***********************************************”);
    }
    public static void swap (CallByRef cbr2)
    {
        int temp;
        temp = cbr2.num1;
        cbr2.num1 = cbr2.num2;
        cbr2.num2 = temp;
       
        System.out.println(“Value of num1 in swap :”+cbr2.num1);
        System.out.println(“Value of num2 in swap :”+cbr2.num2);
        System.out.println(“***********************************************”);
    }
}

/***** PROGRAM TO DEMONSTRATE CALL BY VALUE *****/
public class CallByVal
{
    public static void main()
    {
        int num1 = 100, num2 = 200;
        System.out.println(“***** Program to demonstrate call by value *****”);
        System.out.println(“Value of num1 before call to swap :”+num1);
        System.out.println(“Value of num2 before call to swap :”+num2);
       
        swap(num1, num2); // calling swap method by value
       
        System.out.println(“Value of num1 after call to swap :”+num1);
        System.out.println(“Value of num2 after call to swap :”+num2);
    }
    public static void swap (int num11,int num22)
    {
        int temp;
        temp = num11;
        num11 = num22;
        num22 = temp;
       
        System.out.println(“Value of num1 in swap :”+num11);
        System.out.println(“Value of num2 in swap :”+num22);
       
    }
   
}