关于Executor 接口

public interface Executor {
    /**
     * @param command the runnable task
     * @throws RejectedExecutionException if this task cannot be
     * accepted for execution
     * @throws NullPointerException if command is null
     */
    void execute(Runnable command);

}

对于Executor 接口不甚理解，在此mark下

/** * ArrayDeque不是线程安全的，所以，用作堆栈时快于 Stack，在用作队列时快于 LinkedList * */public class MyExcutor implements Executor{private final Queue<Runnable> tasks = new ArrayDeque<Runnable>();private final Executor executor;private Runnable active;public MyExcutor(Executor executor){this.executor = executor;}@Overridepublic synchronized void execute(final Runnable command) {tasks.offer(new Runnable() {@Overridepublic void run() {try {command.run();} finally {scheduleNext();}}});if(active == null){scheduleNext();}}protected synchronized void scheduleNext() {if((active = tasks.poll()) != null){executor.execute(active);}}public void display(){if(tasks.isEmpty()){System.out.println("this is null");}for(Runnable r : tasks){System.out.println(r.toString());}}public static void main(String[] args) {Runnable r1 = new Runnable() {@Overridepublic void run() {int i = 0;System.out.println(" i = " + (++i));}};Runnable r2 = new Runnable() {@Overridepublic void run() {int a = 3;System.out.println(" a = " + (++a));}};Runnable r3 = new Runnable() {@Overridepublic void run() {int b = 7;System.out.println(" b = " + (++b));}};MyExcutor m = new MyExcutor(new Executor() {@Overridepublic void execute(Runnable command) {command.run();}});m.execute(r1);m.execute(r2);m.execute(r3);m.display();}}