Semaphore maintaining the number of threads currently accessing itself

The number of users who can achieve traffic control while accessing files

import java.util.concurrent.executorservice;import java.util.concurrent.executors;import  java.util.concurrent.semaphore;public class semaphoretest {    public  Static void main (String[] args)  {         Executorservice service = executors.newcachedthreadpool ();         final  semaphore sp = new semaphore (3);//Create Semaphore semaphore, initialize license size 3         runnable runnable = new runnable () {             public void run () {             try {                 sp.acquire ()///request permission to continue execution if a license is available, minus 1 of the license. Otherwise enter the blocking state             } catch  (INTERRUPTEDEXCEPTION&NBSP;E1)  {                 e1.printstacktrace ();             }        &NBSP;&NBSP;&NBSP;&NBSP;&NBSP;SYSTEM.OUT.PRINTLN ("Thread"  + thread.currentthread (). GetName ()  +                        "Enter, currently available"  +  (3-sp.availablepermits ())  +  "concurrency");             try {                 thread.sleep ((Long) (Math.random () *10000));             } catch  (interruptedexception e)  {      &nBsp;          e.printstacktrace ();             }           &NBSP;&NBSP;SYSTEM.OUT.PRINTLN ("Thread"  + thread.currentthread (). GetName ()  +                       " Going away ");                                 sp.release ();//release permission, Number of licenses plus 1            //The following code is sometimes executed inaccurately because it does not synthesize atomic units with the above code &NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;SYSTEM.OUT.PRINTLN ("Threads"  +  Thread.CurrentThread (). GetName ()  +                       "left, currently available"  +  (3-sp.availablepermits ())  +  "concurrency");                              }    };         for (int i=0;i<10;i++) {             service.execute (runnable);  //Submit 10 Quests                     }    }                                                                                                                         }

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Semaphore maintaining the number of threads currently accessing itself