Java Executors newSingleThreadExecutor() Method

The newSingleThreadExecutor() method of Executors class creates an Executor that uses a single worker thread operating off an unbounded queue. (Note however that if this single thread terminates due to a failure during execution before the shutdown, a new one will take its place if needed to execute subsequent tasks.).

Syntax

public static ExecutorService newSingleThreadExecutor()
public static ExecutorService newSingleThreadExecutor(ThreadFactory threadFactory)

Parameter

threadFactory - the factory to use when creating new threads

Returns

the newly created single-threaded Executor

Throws

NullPointerException

Example 1

//import statement
 
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ExecutorsnewSingleThreadExecutorExample1  {
    public static void main(String[] args) {
        System.out.println("current thread : " + Thread.currentThread().getName());

        System.out.println(" Executor Service...");
        ExecutorService ex  = Executors.newSingleThreadExecutor();

        System.out.println("Runnable...");
        Runnable runnable = () -> {
            System.out.println(":: " + Thread.currentThread().getName());
        };

        System.out.println("Submit the task ");
        ex.submit(runnable);
    }
}

Test it Now

Output:

current thread : main
 Executor Service...
Runnable...
Submit the task 
:: pool-1-thread-1

Example 1

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

public class ExecutorsnewSingleThreadExecutorExample2   {

   public static void main(final String[] arguments) throws InterruptedException {
      ExecutorService ex = Executors.newSingleThreadExecutor();

      try {
         ex.submit(new myThread5());
         System.out.println("Shutingdown executor");
         ex.shutdown();
         ex.awaitTermination(10, TimeUnit.SECONDS);
      } catch (InterruptedException e) {
         System.err.println(e);
      } finally {

         if (!ex.isTerminated()) {
            System.err.println("cancel  tasks");
         }
         ex.shutdownNow();
         System.out.println(" finished");
      }
   }

   static class myThread5 implements Runnable {
      
      public void run() {

         try {
            Long duration = (long) (Math.random() * 90);
            System.out.println("Running Task!");
            TimeUnit.SECONDS.sleep(duration);
         } catch (InterruptedException e) {
            e.printStackTrace();
         }
      }
   }
}

Test it Now

Output: