public class isPrime { public static void main(String[] args) throws FileNotFoun

Question

public class isPrime {
   public static void main(String[] args) throws FileNotFoundException
   {   
   isPrime primeNum = new isPrime();
   for(int i=1;i<=9999;i++){
   if ( primeNum.isPrime(i) ) {
   System.out.printf(" Result: The number %d is Prime", i);
   PrintWriter isPrime = new PrintWriter ("Created by John Xiang.txt");
   isPrime.println(i);
   isPrime.close();
   } else {
   System.out.printf(" Result: The number %d is not Prime", i);
   }
   }
   }

How can I print all the prime results to TXT?

Explanation / Answer

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.PrintWriter;

public class isPrime {
   public static void main(String[] args) throws FileNotFoundException {
       isPrime primeNum = new isPrime();

       try {
           File file = new File("Xiang.txt");
           if (!file.exists()) {
               file.createNewFile();
           }
           FileWriter fw = new FileWriter(file.getAbsoluteFile());
           BufferedWriter bw = new BufferedWriter(fw);
           for (int i = 1; i <= 9999; i++) {
               if (primeNum.isPrime(i)) {
                   System.out.printf(" Result: The number %d is Prime", i);
                   PrintWriter isPrime = new PrintWriter(
                           "Created by John Xiang.txt");
                   isPrime.println(i);
                   bw.write(i + " ");

                   isPrime.close();
               } else {
                   System.out.printf(" Result: The number %d is not Prime",
                           i);
               }
           }
           bw.close();
       } catch (Exception e) {

           e.printStackTrace();
       }
   }

   /**
   * checks whether an int is prime or not.
   *
   * @param n
   * @return
   */
   public boolean isPrime(int n) {
       for (int i = 2; i < n; i++) {
           if (n % i == 0)
               return false;
       }
       return true;
   }

}

Xiang.txt
1
2
3
5
7
11
13
17
19
23
29
31
37
41
43
47
.
.
.
9941
9949
9967
9973

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