Four ways to create a Java thread pool

Java provides four thread pools through executors, namely:
Newcachedthreadpool creates a cacheable thread pool that can flexibly reclaim idle threads if the thread pool length exceeds the processing needs, and creates a new thread if it is not recyclable.

Newfixedthreadpool creates a thread pool that controls the maximum number of concurrent threads, and the excess threads wait in the queue.

Newscheduledthreadpool creates a fixed-line pool that supports timed and recurring task execution.

Newsinglethreadexecutor creates a single threaded thread pool that performs tasks with only a single worker thread, ensuring that all tasks are executed in the specified order (FIFO, LIFO, priority).

Read more about blog Java Concurrent Programming: using the thread pool

1.newCachedThreadPool the thread pool here is infinitely large, and when a thread finishes the task, it can then complete the task that will be assigned instead of creating a new thread.

 Public Static voidMain (string[] args) {Executorservice Cachedthreadpool=Executors.newcachedthreadpool ();  for(inti = 0; I < 10; i++) {              Final intindex =i; Try{Thread.Sleep (10); } Catch(interruptedexception e) {e.printstacktrace (); } cachedthreadpool.execute (NewRunnable () { Public voidrun () {System.out.println (index);          }              }); }      }

2.newFixedThreadPool

 Public Static voidMain (string[] args) {Executorservice Fixedthreadpool= Executors.newfixedthreadpool (3);  for(inti = 0; I < 10; i++) {              Final intindex =i; Fixedthreadpool.execute (NewRunnable () { Public voidrun () {Try{System.out.println (index); Thread.Sleep (10); } Catch(interruptedexception e) {e.printstacktrace ();          }                  }              }); }      }  

3.newScheduledThreadPoo

 public  static  void   main (string[] args) {scheduledexecutorservice Scheduledthreadpool  = Executo          Rs.newscheduledthreadpool (5 for  (int  i = 0; i <; I++ new   Runnable () { public  void   run () {System.out.println (" Delay 3 seconds                  ");          }},  3

4.newSingleThreadExecutor executes thread tasks sequentially but unlike single threads, the thread pool can only have one thread, which is routines by the other line after death.

 Public Static voidMain (string[] args) {Executorservice singlethreadexecutor=Executors.newsinglethreadexecutor ();  for(inti = 0; I < 10; i++) {              Final intindex =i; Singlethreadexecutor.execute (NewRunnable () { Public voidrun () {/*System.out.println (index);*/                      Try{System.out.println (index); Thread.Sleep (2000); } Catch(interruptedexception e) {e.printstacktrace ();          }                  }              }); }      }  

Four ways to create a Java thread pool