This post shows how you can generate and display prime numbers in Java in the given range.

A number is a prime number if can be divided either by 1 or by the number itself. So every number with in the given range has to be divided starting from 2 till number/2 in the loop. You only need to run your loop from 2 to N/2 (where N is the passed number), reason being no number is completely divisible by a number more than its half.

### Java code to display prime numbers within the given range

import java.util.Scanner; public class DisplayPrime { public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter start number for displaying prime numbers- "); int start = sc.nextInt(); // Since 1 and 0 are not considered prime if(start == 0 || start == 1){ start = 2; } System.out.println("Enter end number for displaying prime numbers- "); int end = sc.nextInt(); for(int i = start; i <= end; i++){ if(isPrimeNumebr(i)){ System.out.print(i + " "); } } } private static boolean isPrimeNumebr(int num){ boolean flag = true; for(int i = 2; i <= num/2; i++){ // No remainder means completely divides if(num % i == 0){ flag = false; break; } } return flag; } }

__Output__Enter start number for displaying prime numbers- 1 Enter end number for displaying prime numbers- 20 2 3 5 7 11 13 17 19 Enter start number for displaying prime numbers- 20 Enter end number for displaying prime numbers- 100 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97

That's all for the topic **Display Prime Numbers in Java**. If something is missing or you have something
to share about the topic please write a comment.

**You may also like**

- How to Reverse a Number in Java
- Java Program to Swap Two Numbers Without Using Third Variable
- Java Program to Find Common Element Between Two Arrays
- Spring Component Scanning Example
- Why wait(), notify() and notifyAll() Methods Must be Called From a Synchronized Method or Block
- Object Class in Java
- ArrayList Vs LinkedList in Java
- Semaphore in Java With Examples