Thread pool (4) executors.newscheduledthreadpool-only executes 1 times

Example 1: After 3 seconds delay, only 1 times are performed

Scheduledexecutorservice es = Executors.newscheduledthreadpool (5); Log.info ("Start Time"); Try {             for(inti = 0; I < 20; i++) {Runnable syncrunnable=NewRunnable () {@Override Public voidrun () {Log.info (Thread.CurrentThread (). GetName ());                }                }; Es.schedule (syncrunnable,3000, Timeunit.milliseconds); }        } finally{es.shutdown (); }

Operation Result:

            10:41:39.589 start time             10:41:42.595 pool-1-thread-1            10:41:42.595 pool-1-thread-2            10:41:42.595 Pool-1-thread-3            10:41:42.595 pool-1-thread-4            10:41:42.596 pool-1-thread-2            10:41:42.596 Pool-1-thread-5            10:41:42.596 pool-1-thread-1            10:41:42.596 pool-1-thread-3            10:41:42.597 Pool-1-thread-4            10:41:42.597 pool-1-thread-2            10:41:42.597 pool-1-thread-5            10:41:42.597 Pool-1-thread-1            10:41:42.598 pool-1-thread-3            10:41:42.598 pool-1-thread-4            10:41:42.598 Pool-1-thread-2            10:41:42.599 pool-1-thread-5            10:41:42.599 pool-1-thread-1            10:41:42.600 Pool-1-thread-3            10:41:42.600 pool-1-thread-4            10:41:42.600 pool-1-thread-2

Threadpoolexecutor of the call:

 Public Scheduledthreadpoolexecutor (int  corepoolsize) {        Super(Corepoolsize, Integer.max_ VALUE, 0, nanoseconds,              new  delayedworkqueue ());    }

Corepoolsize=5,maximumpoolsize=integer.max_value

Keepalivetime=0 nanoseconds

Allowcorethreadtimeout=false (default)

Use delay queue delayedworkqueue

So

• The number of threads in the thread pool is always 5, permanently surviving
• For new tasks, when the queue is not full, the queue is inserted, and when the queue is full, the default execution AbortPolicy, which throws an exception.
• Support Thread Reuse

So, like Newfixedthreadpool

Public scheduledthreadpoolexecutor (int corepoolsize) {super (corepoolsize, Integer.max_value, 0, nanoseconds,    New Delayedworkqueue ()); }

Thread pool (4) executors.newscheduledthreadpool-only executes 1 times