java - How can I create separate output lines, depending on the Thread the output is coming from? -

i have program implements 2 different sort algorithms. testing both algorithms in parallel launching them in separate threads. able view results of sort operation, as taking place in each thread, , trying keep these results on same line (for each thread).

ex:

arr1= 3 5 8 11 16 ... (sort output thread 1)
arr2= 4 7 9 10 17 ... (sort output thread 2)

i have accomplishing thread.sleep(xxx) after main logic runs, works when have 1 thread. if put delay in both threads displays this:

arr1=
arr2=arr1 [i] arr2[i] arr1[i+1] arr2[i+2] ...

in other words, output both sorts being displayed on same line.

here code:

import java.util.priorityqueue;  class sortarebubblesort extends thread {     int nre, min, max;      public sortarebubblesort(int nre, int min, int max) {         this.nre = nre;         this.min = min;         this.max = max;     }      public void run() {         int[] x = new int[nre];         (int = 0; < x.length - 1; i++)             x[i] = min + (int) (math.random() * ((max - min) + 1));         boolean domore = true;         while (domore) {             domore = false;             (int = 0; < x.length - 1; i++) {                 if (x[i] > x[i + 1]) {                     int temp = x[i];                     x[i] = x[i + 1];                     x[i + 1] = temp;                     domore = true;                  }             }         }          system.out.println("\nhere sorted array bubblesort:");         (int = 0; < x.length; i++)             system.out.print(x[i] + " ");         system.out.print("\n");      } }  class sortareheapsort extends thread {     int nre, min, max;      public sortareheapsort(int nre, int min, int max) {         this.nre = nre;         this.min = min;         this.max = max;     }      public void run() {         int[] x = new int[nre];         (int = 0; < x.length - 1; i++)             x[i] = min + (int) (math.random() * ((max - min) + 1));          priorityqueue<integer> pqueue = new priorityqueue<integer>();         (int w : x)             pqueue.add(w);         (int k = 0; k < x.length; k++)             x[k] = pqueue.poll();          // print array         system.out.println("\nhere sorted array heapsort:");         (int w : x)             system.out.print(w + "  ");     } }  public class testthread {     public static void main(string args[]) {         sortarebubblesort fir1;         sortareheapsort fir2;         fir1 = new sortarebubblesort(10, 1, 100);         fir2 = new sortareheapsort(10, 100, 200);         fir1.start();         fir2.start();     } } 

any or guidance appreciated, thanks.

try make synchronized static method print array, first thread finishes job gets lock , release when prints entire array.