How to find prime numbers for given number using java

package com.onlinecodegeek.java.numbers;import java.util.Scanner;/** * This program explains  to list prime numbers for the given number *  */public class ComputePrimes{  static int MAX = 10000;  public static void main(String[] args) {   Scanner scan = new Scanner(System.in);   int firstNumber=2, lastNumber=0; System.out.println("Enter the number to list of prime number range"); lastNumber = scan.nextInt();     long[] prime = new long[MAX];    long stop = lastNumber;    if (args.length == 1) {      stop = Long.parseLong(args[0]);    }    prime[1] = firstNumber;       // P1 (ignore prime[0])    long n = firstNumber+1;       // odd candidates    int j = 1;        // numberFound    boolean isPrime = true;  // for 3    do {      if (isPrime) {        if (j == MAX-1) {          // Grow array dynamically if needed          long[] np = new long[MAX * 2];          System.arraycopy(prime, 0, np, 0, MAX);          MAX *= 2;          prime = np;        }        prime[++j] = n;  // P2        isPrime = false;      }      n += 2;        // P4      for (int k = 2; k <= j && k < MAX; k++) {  // P5, P6, P8        long q = n / prime[k];        long r = n % prime[k];        if (r == 0) {                break;        }        if (q <= prime[k]) {    // P7          isPrime = true;          break;        }      }          } while (n < stop);        // P3    for (int i=1; i<=j; i++)      System.out.println(prime[i]);  }}

Enter the number to list of prime number range323

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