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copied!<p>The best way to handle this is to "serialize" your tasks. You can do this with a message queue - a class that maintains a <code>Vector</code> of message objects (tasks) and runs code based on each message. The queue runs on a thread that processes each task (message) in series. You create a simple message class for the different tasks - read RMS etc. A message can be an <code>Integer</code> if you like that wraps a number. The operation of adding and retrieving messages is synchronized but the code than does the tasks is not and runs on a simple switch block. The benefit of serializing your tasks is you don't have to worry about concurrency. Here is some of the essential code from a class I use to do this. </p> <pre><code>class MessageQueue implements Runnable{ Vector messages; Thread myThread; volatile boolean stop; public void start() { stop=false; myThread=new Thread(this); myThread.start(); } // add message to queue - this is public public synchronized void addMessage(Message m) { messages.addElement(m); if(stop) { start(); } else { // wake the thread notify(); } } // get next message from queue - used by this thread private synchronized Message nextMessage() { if(stop) return null; if(messages.isEmpty()) { return null; } else { Message m=(Message)messages.firstElement(); messages.removeElementAt(0); return m; } } public void run() { while (!stop) { // make thread wait for messages if (messages.size() == 0) { synchronized (this) { try { wait(); } catch (Exception e) { } } } if (stop) { // catch a call to quit return; } processMessage(); } } } // all the tasks are in here private void processMessage() { Message m = nextMessage(); switch (m.getType()) { case Message.TASK1: // do stuff break; case Message.TASK2: // do other stuff break; case Message.TASK3: // do other other stuff break; default: //handle bad message } } } </code></pre>

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