自定义线程工厂：

public class CustomThreadFactory implements ThreadFactory {    private static final Logger LOGGER = LoggerFactory.getLogger(CustomThreadFactory.class);    public static Thread.UncaughtExceptionHandler LOGGER_UNCAUGHT_EXCEPTION_HANDLER = (t, e) -> LOGGER.error(t.getName(), e);    private static final AtomicInteger poolNumber = new AtomicInteger(1);    private final ThreadGroup group;    private final AtomicInteger threadNumber = new AtomicInteger(1);    private final String namePrefix;    private CustomThreadFactory(ThreadGroup group, String prefix) {        if (group == null) {            SecurityManager s = System.getSecurityManager();            this.group = (s != null) ? s.getThreadGroup() : Thread.currentThread().getThreadGroup();        } else {            this.group = group;        }        if (prefix == null) {            this.namePrefix = "custom-" + poolNumber.getAndIncrement() + "-thread-";        } else {            this.namePrefix = prefix + "-pool_" + poolNumber.getAndIncrement() + "-thread-";        }    }    public CustomThreadFactory(String prefix) {        this(null, prefix);    }    @Override    public Thread newThread(Runnable r) {        // 线程组中活跃的线程数//        this.group.activeCount();        Thread t = new Thread(this.group, r, this.namePrefix + this.threadNumber.getAndIncrement(), 0);        t.setDaemon(true);        t.setUncaughtExceptionHandler(LOGGER_UNCAUGHT_EXCEPTION_HANDLER);        if (t.getPriority() != Thread.NORM_PRIORITY) {            t.setPriority(Thread.NORM_PRIORITY);        }        return t;    }}

单例模式自定义线程池：

public class MyAsyncExecutor extends ThreadPoolExecutor {    private static final Logger LOGGER = LoggerFactory.getLogger(MyAsyncExecutor.class);    private MyAsyncExecutor() {        super(Runtime.getRuntime().availableProcessors() * 5,                500,                1L,                TimeUnit.MINUTES,                new LinkedBlockingQueue<>(1000),                new CustomThreadFactory("MyAsync"),                (r, e) -> LOGGER.error("{}", e.getActiveCount()));    }    public static MyAsyncExecutor instance() {        return Holder.INSTANCE;    }    private static class Holder {        private static MyAsyncExecutor INSTANCE = new MyAsyncExecutor();    }}