java-Thread Pool-Tool class __JDK

Summarize the use of the four common thread pools that the JDK takes with you

Package thread.pool;
Import Java.util.concurrent.ExecutorService;
Import java.util.concurrent.Executors;
Import Java.util.concurrent.ScheduledExecutorService;

Import Java.util.concurrent.TimeUnit;

    public class Threadpoolutil {static Executorservice cachedthreadpool;

    Static Executorservice Fixedthreadpool;

    Static Scheduledexecutorservice Scheduledthreadpool;

    Static Executorservice Singlethreadpool; Static Executorservice Cachedthreadpoolrun (Runnable Runnable) {if (Cachedthreadpool = null) cachedth
        Readpool = Executors.newcachedthreadpool ();
        Cachedthreadpool.submit (runnable);
    return cachedthreadpool;
            public static Executorservice Fixedthreadpoolrun (Runnable Runnable) {if (Fixedthreadpool = null)
        Fixedthreadpool = Executors.newfixedthreadpool (Runtime.getruntime (). Availableprocessors ());
        Fixedthreadpool.submit (runnable);
    return fixedthreadpool; } pUblic static Executorservice Scheduledthreadpoolrun (Runnable Runnable, long delay, timeunit unit) {if (Scheduledt
                    Hreadpool = = null) Scheduledthreadpool = Executors.newscheduledthreadpool (Runtime.getruntime ()
        . Availableprocessors ());
        Scheduledthreadpool.schedule (runnable, delay, unit);
    return scheduledthreadpool;
            public static Executorservice Singlethreadpoolrun (Runnable Runnable) {if (Singlethreadpool = null)
        Singlethreadpool = Executors.newsinglethreadexecutor ();
        Singlethreadpool.submit (runnable);
    return singlethreadpool;
        public static void Main (string[] args) {final Long starttime = System.currenttimemillis ();

        Executorservice executorservice = null;
            for (int i = 0; i < 1000000 i++) {//System.out.println (Finali);
            final int finali = i;
            Runnable task = ()-> System.out.println (Finali); ExecUtorservice = Threadpoolutil.fixedthreadpoolrun (Task);
        } if (Executorservice!= null) {Executorservice.shutdown (); } while (true) {if (executorservice.isterminated ()) {System.out.println ("All child threads are ended" 。
                ");
            Break
        } final Long stoptime = System.currenttimemillis ();
        System.out.println ("---------------------------");


    System.out.println (Stoptime-starttime); }

}