With this example we are going to demonstrate how to create a daemon Thread. We have implemented a class, MyDaemonThread, that implements the Runnable, as described below:
- The runnable creates a new Thread, marks it as a daemon, using
setDaemon(boolean on)API method of Thread, and then begins the thread’s execution calling itsstart()API method. - The class overrides the
run()method of Runnable, where it sleeps forever. We create a new instance ofMyDaemonThreadclass in amain()method. The method checks if the thread is a daemon, usingisDaemon()method ofMyDaemonThreadand if so, it sleeps and then exits since the daemon thread is the only one running.
Let’s take a look at the code snippet that follows:
01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 | package com.javacodegeeks.snippets.core;class MyDaemonThread implements Runnable { Thread thrd; MyDaemonThread() { thrd = new Thread(this); thrd.setDaemon(true); thrd.start(); } public boolean isDaemon() { return thrd.isDaemon(); } @Override public void run() { try {while (true) { System.out.print("."); Thread.sleep(100);} } catch (Exception ex) {System.out.println("MyDaemon interrupted."); } }}public class DeamonThreadExample { public static void main(String args[]) throws Exception { MyDaemonThread deamonThread = new MyDaemonThread(); if (deamonThread.isDaemon()) {System.out.println("Daemon thread."); } Thread.sleep(10000); System.out.println("nMain thread ending."); }} |
Output:
Daemon thread.
.....................................................................................................
Main thread ending.
This was an example of how to create a daemon Thread in Java.
