JavaJDK多任务执行框架（六）

约定不等于承诺〃 2021-12-01 23:30 263阅读 0赞

![1001363-20190513123529079-1955513393.png][]

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class Temp extends Thread {
        public void run() {
            System.out.println("run");
        }
    }
    public class UseExecutors {
        public static void main(String[] args) {
            ExecutorService pool = Executors.newSingleThreadExecutor();
            //ThreadPoolExecutor
            Temp command = new Temp();
            ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1);
    
            ScheduledFuture<?> scheduleTask = scheduler.scheduleWithFixedDelay(command, 5, 1, TimeUnit.SECONDS);
        }
    }

![1001363-20190513175859226-1135726750.png][]

import java.util.concurrent.ArrayBlockingQueue;
    import java.util.concurrent.ThreadPoolExecutor;
    import java.util.concurrent.TimeUnit;
    
    public class UseThreadPoolExecutor1 {
        public static void main(String[] args) {
            /**
             * 在使用有界队列时，若有新的任务需要执行，如果线程池实际线程数小于corePoolSize，则优先创建线程，
             * 若大于corePoolSize，则会将任务加入队列，
             * 若队列已满，则在总线程数不大于maximumPoolSize的前提下，创建新的线程，
             * 若线程数大于maximumPoolSize，则执行拒绝策略。或其他自定义方式。
             *
             */
            ThreadPoolExecutor pool = new ThreadPoolExecutor(
                    1, 				//coreSize
                    2, 				//MaxSize
                    60, 			//60
                    TimeUnit.SECONDS,
                    new ArrayBlockingQueue<Runnable>(3)			//指定一种队列 （有界队列）
                    //new LinkedBlockingQueue<Runnable>()
                    , new MyRejected()
                    //, new DiscardOldestPolicy()
            );
    
            MyTask mt1 = new MyTask(1, "任务1");
            MyTask mt2 = new MyTask(2, "任务2");
            MyTask mt3 = new MyTask(3, "任务3");
            MyTask mt4 = new MyTask(4, "任务4");
            MyTask mt5 = new MyTask(5, "任务5");
            MyTask mt6 = new MyTask(6, "任务6");
    
            pool.execute(mt1);
            pool.execute(mt2);
            pool.execute(mt3);
            pool.execute(mt4);
            pool.execute(mt5);
            pool.execute(mt6);
    
            pool.shutdown();
        }
    }

import java.util.concurrent.RejectedExecutionHandler;
    import java.util.concurrent.ThreadPoolExecutor;
    
    public class MyRejected implements RejectedExecutionHandler {
        public MyRejected(){
        }
    
        @Override
        public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) {
            System.out.println("自定义处理..");
            System.out.println("当前被拒绝任务为：" + r.toString());
        }
    }

public class MyTask implements Runnable{
        private int taskId;
        private String taskName;
    
        public MyTask(int taskId, String taskName){
            this.taskId = taskId;
            this.taskName = taskName;
        }
    
        public int getTaskId() {
            return taskId;
        }
    
        public void setTaskId(int taskId) {
            this.taskId = taskId;
        }
    
        public String getTaskName() {
            return taskName;
        }
    
        public void setTaskName(String taskName) {
            this.taskName = taskName;
        }
    
        @Override
        public void run() {
            try {
                System.out.println("run taskId =" + this.taskId);
                Thread.sleep(5*1000);
                //System.out.println("end taskId =" + this.taskId);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    
        public String toString(){
            return Integer.toString(this.taskId);
        }
    }

import java.util.concurrent.ArrayBlockingQueue;
    import java.util.concurrent.BlockingQueue;
    import java.util.concurrent.ExecutorService;
    import java.util.concurrent.LinkedBlockingQueue;
    import java.util.concurrent.ThreadPoolExecutor;
    import java.util.concurrent.TimeUnit;
    import java.util.concurrent.atomic.AtomicInteger;
    
    public class UseThreadPoolExecutor2 implements Runnable{
    
    	private static AtomicInteger count = new AtomicInteger(0);
    	
    	@Override
    	public void run() {
    		try {
    			int temp = count.incrementAndGet();
    			System.out.println("任务" + temp);
    			Thread.sleep(2000);
    		} catch (InterruptedException e) {
    			e.printStackTrace();
    		}
    	}
    	
    	public static void main(String[] args) throws Exception{
    		//System.out.println(Runtime.getRuntime().availableProcessors());
    		BlockingQueue<Runnable> queue = 
    				//new LinkedBlockingQueue<Runnable>();
    				new ArrayBlockingQueue<Runnable>(10);
    		ExecutorService executor  = new ThreadPoolExecutor(
    					5, 		//core
    					10, 	//max
    					120L, 	//2fenzhong
    					TimeUnit.SECONDS,
    					queue);
    		
    		for(int i = 0 ; i < 20; i++){
    			executor.execute(new UseThreadPoolExecutor2());
    		}
    		Thread.sleep(1000);
    		System.out.println("queue size:" + queue.size());		//10
    		Thread.sleep(2000);
    	}
    }

Executor框架：

![1001363-20190514124434308-2060460214.png][]

转载于:https://www.cnblogs.com/sunliyuan/p/10856001.html

[1001363-20190513123529079-1955513393.png]: /images/20211201/617e3b06a0e540f29a0eabc9cb7f3898.png
[1001363-20190513125902912-855598747.png]: /images/20211201/5893516c1b4549019db20722a1417745.png
[1001363-20190513175859226-1135726750.png]: /images/20211201/8cd04e61cbc547db92ea7a5fdd17d482.png
[1001363-20190514124434308-2060460214.png]: /images/20211201/184821b9c70c4805959bbdf19e08bcd1.png