// JavaDaemonTest  -  A test program that can be used as a dummy daemon

import java.util.Date;
import java.text.SimpleDateFormat;

public class JavaDaemonTest {

private static final int shutdownTime = 2;                 // shutdown hook delay time in seconds

public static void main (String[] args) {
   log ("JavaDaemonTest started");
   System.err.println (getTimeStamp()+" This is output to StdErr...");
   Thread runtimeHookThread = new Thread() {
      public void run() {
         shutdownHook(); }};
   Runtime.getRuntime().addShutdownHook (runtimeHookThread);
   try {
      while (true) {
         Thread.sleep (3000);
         log ("running"); }}
    catch (Throwable t) {
      log ("Exception: "+t.toString()); }}

private static void shutdownHook() {
   log ("ShutdownHook started");
   long t0 = System.currentTimeMillis();
   while (true) {
      try {
         Thread.sleep (500); }
        catch (Exception e) {
         log ("Exception: "+e.toString());
         break; }
      if (System.currentTimeMillis() - t0 > shutdownTime*1000) break;
      log ("shutdown"); }
   log ("ShutdownHook completed"); }

private static void log (String msg) {
   System.out.println (getTimeStamp()+" "+msg); }

private static String getTimeStamp() {
   SimpleDateFormat f = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
   return f.format(new Date()); }

} // end class JavaDaemonTest