Java Program to swap two numbers without using temp variable

public class SwapNoTemp
{

public static void main(String[] args)
{
try
{
int a=Integer.parseInt(args[0]);
int b=Integer.parseInt(args[1]);

System.out.println("Values before swapping\n");
System.out.println("a="+a+" b="+b);

a=a+b;
b=a-b;
a=a-b;

System.out.println("Values after swapping\n");
System.out.println("a="+a+" b="+b);
}
catch(Exception e)    
{
System.out.println("Error! Please see the below stack trace\n\n");
e.printStackTrace();
}
}
}