"Java Multithreading" Cyclicbarrier Synchronization helper Class

Cyclicbarrier is a synchronization helper class under the Java.util.concurrent package, similar to Countdownlatch, and is also a synchronization counter.

The difference between Countdownlatch and the other is:
The Countdownlatch await () method is blocked because the countdown () method that waits for a certain number of calls can be done on the same thread;

The Cyclicbarrier await () method is blocked because a certain number of threads are waiting to invoke the await () method, which must be called on a different thread

So, to summarize:

Countdownlatch is waiting for a certain number of calls to Countdown (), otherwise the thread that calls the await () method is blocked.

Cyclicbarrier is waiting for a certain number of threads to call await (), otherwise all threads calling await () will block.

Demo Code:

import java.util.random;import java.util.concurrent.brokenbarrierexception;import  java.util.concurrent.cyclicbarrier;import java.util.concurrent.executorservice;import  java.util.concurrent.executors;  public class testcyclicbarrier {         public static void main (String[] args)  {                 executorservice exec  = executors.newcachedthreadpool ();                        /**          *  indicates that the Cyclicbarrier await () method must be performed on every 5 threads,  to execute the Run method in Cyclicbarrier;          *  if there are less than 5 threads executing the await () method,  then the thread that executes the await () method will block,   until the 5th thread executes the await () method;          */        final cyclicbarrier  Cyclicbarrier = new cyclicbarrier (5, new runnable () {               public void run ()               {                   system.out.println ("Everybody's Here, start Happy");               }         });                  final random random=new random ();         for (int  i = 0; i < 5; i++)         {       &nbsP;     exec.execute (new runnable () {                   public void run ()                   {                        try                      {                           thread.sleep (RANDOM.NEXTINT (1000 ));                       }                      catch  (interruptedexception e)                       {                            e.printstacktrace ();                       }                       system.out.println ( Thread.CurrentThread (). GetName () + "Come, Other buddies");                       try                      {                       //waits for the remaining threads to execute the await () method;                          cyclicbarrier.await ();                     }                      catch (InterruptedException  e)                       {                           e.printstacktrace ();                        }                      catch (brokenbarrierexception e)                       {                            E.printstacktrace ();                       }                      system.out.println (Thread.currentThread (). GetName ( + "Say:  people qi,  play to go ...");                   }            });     &nBsp;     }          exec.shutdown () ;       }    }

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"Java Multithreading" Cyclicbarrier Synchronization helper Class