Prime Number Program : Java Programming

This program explain you how to check the number is prime or not if user input the value from keyboard. Here is the source code :

import java.io.*;



class PrimeNumber {

public static void main(String[] args) throws Exception{


int i;

BufferedReader bf = new BufferedReader(

new InputStreamReader(System.in));


System.out.println("Enter number to Check:");

int num = Integer.parseInt(bf.readLine());

System.out.println("Prime number: ");


for (i=1; i < num; i++ ){

int j;

for (j=2; j<i; j++){


int n = i%j;

if (n==0){

break;

}

}


if(i == j){

System.out.print(" "+i);

}

}


}

}

Explanation : public static void main(String args[])

What is the work of public static void main(String args[]) method in Java. Here is the explanation :

• public : The public method can be accessed outside the class
• static : We must have an instance to access the class method.
• void : There is no need by application to return value. JVM launcher do this with it exists.
• main() : It is the entry point for the java application.
• String args[] : It holds optional arguments passed to the class.