Impossible to make a cached thread pool with a size limit?

Question

It seems to be impossible to make a cached thread pool with a limit to the number of threads that it can create.

Here is how static Executors.newCachedThreadPool is

Answer 1

Here is another solution. I think this solution behaves as you want it to (though not proud of this solution):

final LinkedBlockingQueue queue = new LinkedBlockingQueue() {
    public boolean offer(Runnable o) {
        if (size() > 1)
            return false;
        return super.offer(o);
    };

    public boolean add(Runnable o) {
        if (super.offer(o))
            return true;
        else
            throw new IllegalStateException("Queue full");
    }
};

RejectedExecutionHandler handler = new RejectedExecutionHandler() {         
    public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) {
        queue.add(r);
    }
};

dbThreadExecutor =
        new ThreadPoolExecutor(min, max, 60L, TimeUnit.SECONDS, queue, handler);