线程池四种拒绝机制实现及执行日志

news/2024/4/26 5:27:58/文章来源:https://blog.csdn.net/weixin_42749765/article/details/130379555

创建线程池

    public static ExecutorService executor = new ThreadPoolExecutor(2,2, 60L, TimeUnit.SECONDS,new LinkedBlockingQueue<Runnable>(3), Executors.defaultThreadFactory(),
//            new ThreadPoolExecutor.AbortPolicy()
//     new ThreadPoolExecutor.DiscardPolicy()new ThreadPoolExecutor.DiscardOldestPolicy()
//            new ThreadPoolExecutor.CallerRunsPolicy());

测试代码

 @Testpublic void t1() throws InterruptedException {for (int i = 0; i < 9; i++) {String finalI = i+"";try {ex(finalI);}catch (RejectedExecutionException e){System.out.println(finalI+" error = "+e);Thread.sleep(2);ex(finalI+" 重新执行");}}Thread.sleep(1000*5);}

运行线程

 public static void ex(String i) throws RejectedExecutionException{String finalI = i;executor.execute(new Runnable() {private String finalC = finalI;@Overridepublic void run() {
//                System.out.println(Thread.currentThread().getName()+" == start =="+ finalC);try {Thread.sleep(2);} catch (InterruptedException e) {System.out.println("error = "+e);}System.out.println(Thread.currentThread().getName()+" == success =="+ finalC);}});}

全量代码


import org.junit.jupiter.api.Test;import java.util.concurrent.*;public class TeTh {public static ExecutorService executor = new ThreadPoolExecutor(2,2, 60L, TimeUnit.SECONDS,new LinkedBlockingQueue<Runnable>(3), Executors.defaultThreadFactory(),
//            new ThreadPoolExecutor.AbortPolicy()
//     new ThreadPoolExecutor.DiscardPolicy()new ThreadPoolExecutor.DiscardOldestPolicy()
//            new ThreadPoolExecutor.CallerRunsPolicy());@Testpublic void t1() throws InterruptedException {for (int i = 0; i < 9; i++) {String finalI = i+"";try {ex(finalI);}catch (RejectedExecutionException e){System.out.println(finalI+" error = "+e);Thread.sleep(2);ex(finalI+" 重新执行");}}Thread.sleep(1000*5);}public static void ex(String i) throws RejectedExecutionException{String finalI = i;executor.execute(new Runnable() {private String finalC = finalI;@Overridepublic void run() {
//                System.out.println(Thread.currentThread().getName()+" == start =="+ finalC);try {Thread.sleep(2);} catch (InterruptedException e) {System.out.println("error = "+e);}System.out.println(Thread.currentThread().getName()+" == success =="+ finalC);}});}
}

日志

AbortPolicy 报出异常模式

5 error = java.util.concurrent.RejectedExecutionException: Task org.cc.automaton.security.TeTh$1@172ed45 rejected from java.util.concurrent.ThreadPoolExecutor@79c292[Running, pool size = 2, active threads = 2, queued tasks = 3, completed tasks = 0]
pool-1-thread-2 == success ==1
pool-1-thread-1 == success ==0
7 error = java.util.concurrent.RejectedExecutionException: Task org.cc.automaton.security.TeTh$1@1574691 rejected from java.util.concurrent.ThreadPoolExecutor@79c292[Running, pool size = 2, active threads = 2, queued tasks = 3, completed tasks = 2]
pool-1-thread-2 == success ==2
pool-1-thread-1 == success ==3
pool-1-thread-2 == success ==4
pool-1-thread-1 == success ==5 重新执行
pool-1-thread-2 == success ==6
pool-1-thread-1 == success ==7 重新执行
pool-1-thread-2 == success ==8

DiscardPolicy 放弃机制啥也不处理

pool-1-thread-1 == success ==0
pool-1-thread-2 == success ==1
pool-1-thread-1 == success ==2
pool-1-thread-2 == success ==3
pool-1-thread-1 == success ==4

DiscardOldestPolicy 放弃机制，放弃列队最早进入的

pool-1-thread-1 == success ==0
pool-1-thread-2 == success ==1
pool-1-thread-1 == success ==6
pool-1-thread-2 == success ==7
pool-1-thread-1 == success ==8

CallerRunsPolicy 交给主线程执行

pool-1-thread-2 == success ==1
pool-1-thread-1 == success ==0
main == success ==5
pool-1-thread-1 == success ==3
main == success ==8
pool-1-thread-2 == success ==2
pool-1-thread-1 == success ==4
pool-1-thread-2 == success ==6
pool-1-thread-1 == success ==7