swap two numbers in java code example

Example 1: Java program to swap two numbers using function

import java.util.Scanner;
// java swap function
public class SwapTwoNumberDemo 
{
   int numOne, numTwo;
   public void swapNum(SwapTwoNumberDemo stn)
   {
      int temp;
      temp = stn.numOne;
      stn.numOne = stn.numTwo;
      stn.numTwo = temp;
   }
   public static void main(String[] args) 
   {
      SwapTwoNumberDemo obj = new SwapTwoNumberDemo();
      try
      {
         Scanner sc = new Scanner(System.in);             
         System.out.println("First number : ");
         obj.numOne = sc.nextInt();
         System.out.println("Second number : ");
         obj.numTwo = sc.nextInt();
         obj.swapNum(obj);
         System.out.println("After swapping - numOne : " + obj.numOne + ", numTwo : " + obj.numTwo);
         sc.close();
      }
      catch(Exception ex)
      {
         System.out.println("Exception: " + ex.toString());
      }
   }
}

Example 2: swapping with two variables in java

public class Exercise15 {
  public static void main(String[] args) {
     // int, double, float
   int a, b;
   a = 15;
   b = 27;
   System.out.println("Before swapping : a, b = "+a+", "+ + b);
   a = a + b;
   b = a - b;
   a = a - b;
   System.out.println("After swapping : a, b = "+a+", "+ + b);
 }
 
}

Example 3: java program to swap two numbers

int a, b, c;
a = 5;
b = 3;
System.out.println("Before SWAP a = " + a + ", b = " + b);
c = a;
a = b;
b = c;
System.out.println("After SWAP a = " + a + ", b = " + b);