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POSynchronization in threads for Java
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copied!<p>I have a home grown web server in my app. This web server spawns a new thread for every request that comes into the socket to be accepted. I want the web server to wait until a specific point is hit in the thread it just created. </p> <p>I have been through many posts on this site and examples on the web, but cant get the web server to proceed after I tell the thread to wait. A basic code example would be great. </p> <p>Is the synchronized keyword the correct way to go about this? If so, how can this be achieved? Code examples are below of my app:</p> <p><strong>Web Server</strong></p> <pre><code>while (true) { //block here until a connection request is made socket = server_socket.accept(); try { //create a new HTTPRequest object for every file request HttpRequest request = new HttpRequest(socket, this); //create a new thread for each request Thread thread = new Thread(request); //run the thread and have it return after complete thread.run(); /////////////////////////////// wait here until notifed to proceed /////////////////////////////// } catch (Exception e) { e.printStackTrace(logFile); } } </code></pre> <p><strong>Thread code</strong></p> <pre><code>public void run() { //code here //notify web server to continue here } </code></pre> <p>Update - Final code is as below. The <code>HttpRequest</code> does just call <code>resumeListener.resume()</code> whenever I send a response header (of course also adding the interface as a separate class and the <code>addResumeListener(ResumeListener r1)</code> method in <code>HttpRequest</code>):</p> <p><strong>Web Server portion</strong></p> <pre><code>// server infinite loop while (true) { //block here until a connection request is made socket = server_socket.accept(); try { final Object locker = new Object(); //create a new HTTPRequest object for every file request HttpRequest request = new HttpRequest(socket, this); request.addResumeListener(new ResumeListener() { public void resume() { //get control of the lock and release the server synchronized(locker) { locker.notify(); } } }); synchronized(locker) { //create a new thread for each request Thread thread = new Thread(request); //run the thread and have it return after complete thread.start(); //tell this thread to wait until HttpRequest releases //the server locker.wait(); } } catch (Exception e) { e.printStackTrace(Session.logFile); } } </code></pre>

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