Java useful program

Swap Numbers without Using Third Variable Java

public class swap elements without third variable 

{

public static void main(string[] args)

{                

int num1 = 10;

int num2 = 20;                 

system.out.println("Before Swapping");

system.out.println("Value of num1 is :" + num1);

system.out.println("Value of num2 is :" +num2);

num1 = num1 + num2;

num2 = num1 - num2;

num1 = num1 - num2;                

system.out.println("Before Swapping");

system.out.println("Value of num1 is :" + num1);

system.out.println("Value of num2 is :" +num2);

  }

}

Swap Numbers Java

public class swap elements

{

public static void main(string[] args)

{            

int num1 = 10;

int num2 = 20;

system.out.println("Before Swapping");

system.out.println("Value of num1 is :" + num1);

system.out.println("Value of num2 is :" +num2);

swap(num1, num2);

}

private static void swap(int num1, int num2)

{

int temp = num1;

num1 = num2;

num2 = temp;

           system.out.println("After Swapping");

system.out.println("Value of num1 is :" + num1);

system.out.println("Value of num2 is :" +num2);              

    }

}

Reverse Number using Java

public class reverse number

{

public static void main(string[] args)

{

int number = 1234;

int reversednumber = 0;

int temp = 0;            

while(number > 0)

{

temp = number%10;

reversedNumber = reversedNumber * 10 + temp;

number = number/10;                      

}             

system.out.println("Reversed Number is: " + reversedNumber);

   }

}

Java Interface

interface int

{

public void sayhello();

}

}

public class Javainterfaceexample implements intexample

{

public void sayhello()

{

system.out.println("Hello Visitor !");

}

public static void main(string args[])

{

javainterfaceexample javainterfaceexample = new javainterfaceexample();

javainterfaceexample.sayhello();

   }

}

Java Factorial Using Recursion

import java.io.bufferedreader;

import java.io.ioexception;

import java.io.inputstreamreader;

public class javafactorialusingrecursion

{       

public static void main(string args[]) throws numberformatexception, ioexception

{          

system.out.println("Enter the number: ");

bufferedreader br=new bufferedreader(new inputstreamreader(system.in));

int a = integer.parseint(br.readline());

int result= fact(a);

system.out.println("Factorial of the number is: " + result);

}

static int fact(int b)

{

if(b <= 1)

return 1;

else

return b * fact(b-1);

   }

}

Java Factorial

public class numberfactorial

{

public static void main(string[] args)

{             

int number = 5;           

int factorial = number;          

for(int i =(number - 1); i > 1; i--)

{

factorial = factorial * i;

}       

system.out.println("Factorial of a number is " + factorial);

  }

}

  

Java Class

public class javaclassexample

{

private string name;

{

}

public void setname(string n)

{

name = n;

}

public string getname()

{

return name;

}

public static void main(string args[])

{

object-name = new ;

javaclassexample javaclassexample = new javaclassexample();

javaclassexample.setname("visitor");

system.out.println("hello " + javaclassexample.getname());      

  }

}