创建一个线程工厂

区分其他线程，监控线程。

    class NamedThreadFactory implements ThreadFactory {
        private static final AtomicInteger POOL_NUMBER = new AtomicInteger(1);
        private final AtomicInteger THREAD_NUMBER;
        private final ThreadGroup GROUP;
        private final String NAME_PREFIX;
        private final boolean IS_DAEMON;

        NamedThreadFactory() {
            this("test-thread-factory");
        }

        NamedThreadFactory(String name) {
            this(name, false);
        }

        NamedThreadFactory(String preffix, boolean daemon) {
            this.THREAD_NUMBER = new AtomicInteger(0);
            SecurityManager s = System.getSecurityManager();
            this.GROUP = s != null ? s.getThreadGroup() : Thread.currentThread().getThreadGroup();
            this.NAME_PREFIX = preffix + "-" + POOL_NUMBER.getAndIncrement() + "-thread-";
            this.IS_DAEMON = daemon;
        }

        @Override
        public Thread newThread(Runnable r) {
            Thread t = new Thread(this.GROUP, r, this.NAME_PREFIX + this.THREAD_NUMBER.getAndIncrement(), 0L);
            t.setDaemon(this.IS_DAEMON);
            if (t.getPriority() != Thread.NORM_PRIORITY) {
                t.setPriority(Thread.NORM_PRIORITY);
            }

            return t;
        }
    }