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How to create a thread that runs all the time of my application

EDIT: Now I'm sure the problem is with the    while (true)loop containing all the other commands, as I commented on this, and the application deploys without the attached exception. I'm not sure how important this is, but my implementation is ServletContextListeneras follows:

public class BidPushService implements ServletContextListener{

public void contextInitialized(ServletContextEvent sce) {   
//Some init code not relevant, omitted for clarity
      BidPushThread t= new BidPushThread();
      t.setServletContext(sce.getServletContext());
      t.run();
}

code>

So, now the thread starts when the application is deployed, but since the loop is whilecommented out, it has no real meaning.

I need the thread to run in the background when my application loads and constantly (without a timeout) checks a specific queue for objects. Of course, when there are objects, he “takes care of them,” and then continues to check the queue.

ServletContextListener, , . , java.lang.Thread.

( ). run()

while (true) {
    //some code which doesn't put the thread to sleep ever
}

, java.util.concurrent.TimeOutException. ?

, ? , ServletContextListener.

-, .

!

:

GlassFish: deploy is failing=
    java.util.concurrent.TimeoutException
    at java.util.concurrent.FutureTask$Sync.innerGet(Unknown Source)
    at java.util.concurrent.FutureTask.get(Unknown Source)
    at com.sun.enterprise.jst.server.sunappsrv.SunAppServerBehaviour.publishDeployedDirectory(SunAppServerBehaviour.java:710)
    at com.sun.enterprise.jst.server.sunappsrv.SunAppServerBehaviour.publishModuleForGlassFishV3(SunAppServerBehaviour.java:569)
    at com.sun.enterprise.jst.server.sunappsrv.SunAppServerBehaviour.publishModule(SunAppServerBehaviour.java:266)
    at org.eclipse.wst.server.core.model.ServerBehaviourDelegate.publishModule(ServerBehaviourDelegate.java:948)
    at org.eclipse.wst.server.core.model.ServerBehaviourDelegate.publishModules(ServerBehaviourDelegate.java:1038)
    at org.eclipse.wst.server.core.model.ServerBehaviourDelegate.publish(ServerBehaviourDelegate.java:872)
    at org.eclipse.wst.server.core.model.ServerBehaviourDelegate.publish(ServerBehaviourDelegate.java:708)
    at org.eclipse.wst.server.core.internal.Server.publishImpl(Server.java:2690)
    at org.eclipse.wst.server.core.internal.Server$PublishJob.run(Server.java:272)
    at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)

:

public class BidPushThread extends Thread {
    private ServletContext sc=null;
    @Override
    public void run() {
        if (sc!=null){
            final Map<String, List<AsyncContext>> aucWatchers = (Map<String, List<AsyncContext>>) sc.getAttribute("aucWatchers");
            BlockingQueue<Bid> aucBids = (BlockingQueue<Bid>) sc.getAttribute("aucBids");

              Executor bidExecutor = Executors.newCachedThreadPool(); 
              final Executor watcherExecutor = Executors.newCachedThreadPool();
              while(true)
              {  
                 try // There are unpublished new bid events.
                 {
                    final Bid bid = aucBids.take();
                    bidExecutor.execute(new Runnable(){
                       public void run() {
                          List<AsyncContext> watchers = aucWatchers.get(bid.getAuctionId()); 
                          for(final AsyncContext aCtx : watchers)
                          {
                             watcherExecutor.execute(new Runnable(){
                                public void run() {
                                   // publish a new bid event to a watcher
                                   try {
                                    aCtx.getResponse().getWriter().print("A new bid on the item was placed. The current price "+bid.getBid()+" , next bid price is "+(bid.getBid()+1));
                                } catch (IOException e) {
                                    // TODO Auto-generated catch block
                                    e.printStackTrace();
                                }
                                };
                             });
                          }                           
                       }
                    });
                 } catch(InterruptedException e){}
              }

        }
    }
    public void setServletContext(ServletContext sc){
        this.sc=sc;
    }
}

, " 4 " : "BlockingQueue" , ​​ . , "BlockingQueue"

+5
5

, , -.

, start, run.

public void contextInitialized(ServletContextEvent sce) {   
//Some init code not relevant, omitted for clarity
  BidPushThread t= new BidPushThread();
  t.setServletContext(sce.getServletContext());
  t.start();// run();
}
+3

setDaemon

:

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  • checkAccess
    . SecurityException ( ).

: , , . setDaemon() Thread , , . , Java . , .

+5

. 100% .

, , , . BlockingQueue.

+3
Can't I have a thread which is always running? When the app is removed, 
that thread is stopped by the corresponding event in my ServletContextListener.

" "? ? while (true) {...} . ? Thread.stop()? Java 1.1

setDaemon (true), , -, . , -, . -, -. .

(, InterruptedException volatile "stopNow" ), .

+1

java.langThread.setDaemon(),

0

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