class HystrixThreadPoolMetrics extends HystrixMetrics {

    public static Collection<HystrixThreadPoolMetrics> getInstances() {
        List<HystrixThreadPoolMetrics> threadPoolMetrics = new ArrayList<HystrixThreadPoolMetrics>();
        for (HystrixThreadPoolMetrics tpm: metrics.values()) {
            if (hasExecutedCommandsOnThread(tpm)) {
                threadPoolMetrics.add(tpm);
            }
        }

        return Collections.unmodifiableCollection(threadPoolMetrics);
    }

    private  HystrixThreadPoolMetrics(HystrixThreadPoolKey threadPoolKey, ThreadPoolExecutor threadPool, HystrixThreadPoolProperties properties);

}