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    <p>So a thread pool may or may not be the best usage here because there is no real abstraction of work. However this may an interesting use case for extending Thread. I would handle the communication with simple j.u.c.Lock and j.u.c.Condition. Finally, I would delegate stopping and starting to specific delegation classes that accept a Runnable type as individual constant units of work. </p> <p>The only difference I would is to use stop to shutdown and pause to suspend which the start will just continue the work. For example it could look something like this.</p> <pre><code>public class MedicalDeviceWorkManager { private ConcurrentHashMap&lt;String, DelegatingThread&gt; devices = new ConcurrentHashMap&lt;...&gt;(); public synchronized void registerDevice(String device, Runnable singleUnitOfWork){ DelegatingThread worker = new DelegatingThread(singleUnitOfWork); devices.put(device,worker); worker.start(); } public void startDevice(String device){ devices.get(device).startDevice(); } public void stopDevice(String device){ devices.get(device).stopDevice(); } public void pauseDevice(String device){ devices.get(device).pauseDevice(); } private static class DelegatingThread extends Thread{ final Lock lock = new ReentrantLock(); final Condition condition = lock.newCondition(); final Runnable r; boolean paused = true; boolean stopped =false; private DelegatingThread (Runnable r){ this.r = r; } @Override public void run(){ while(true){ lock.lock(); while(paused) condition.await(); if(stopped) return; lock.unlock(); r.run(); } } private void startDevice(){ lock.lock(); paused = false; condition.signal(); lock.unlock(); } private void pauseDevice(){ lock.lock(); if(!stopped) paused = true; lock.unlock(); } private void stopDevice(){ lock.lock(); stopped= true; paused=false; condition.signal(); lock.unlock(); } } } </code></pre> <p>I understand this is a lot of code to demonstrate but the same principles behind a thread pool holds here. You will always create one thread per device and you reuse when necessary. The runnable would be the single function you run in between the while loop. </p> <p>Also, I didn't include the try/finally semantics for brevity.</p>
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    1. POJava Concurrency - Better Design approach to manage thread life cycle (start/stop)
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    1. CO@Jon V, @Enno Shioji:Thanks for the elegant solutions laid out. I'll look into them.
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    2. COHow many devices might there be? The whole reason for a thread pool is that device-per-client does not scale well past a small number of threads.
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    3. COUpto 100 or 200 devices
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