Java?? ???? ??? ??? ?????? ?? ????? ???? ???? 3?? ??? ? ???? ?????. ??? ??? ???? ?? ??? ? ??? ????.

Java?? ???? ????? ????? ? ?? ??? ????.

1. Thread ???? ?????.

2. Callable ? Future? ???? ?????. ?.

[?? ??:

java ??? ????

]

1. Thread ??? ??Thread ???? ???? ?? ?? ???? ?? ???? ???? ? ??? ???? ???. ?? ??.

class?MyThread?extends?Thread{
????private?static?int?num?=?0;
?????
????public?MyThread(){
????????num++;
????}
?????
????@Override
????public?void?run()?{
????????System.out.println("主動創(chuàng)建的第"+num+"個線程");
????}
}

??? ??? ???? ?? ? ??? ??? ?? ?? start() ???? ?? ???? ??? ? ????. run() ???? ???? ???? ?? ???? ????. run ???? ???? ? ??? ?????. run ???? ???? ?? ????? run ???? ???? ?? ?????. ??? ??? ??? ???? ?? ??? ???? ???? ????.

public?class?Test?{
????public?static?void?main(String[]?args)??{
????????MyThread?thread?=?new?MyThread();
????????thread.start();
????}
}
?
?
class?MyThread?extends?Thread{
????private?static?int?num?=?0;
?????
????public?MyThread(){
????????num++;
????}
?????
????@Override
????public?void?run()?{
????????System.out.println("主動創(chuàng)建的第"+num+"個線程");
????}
}

? ???? start() ???? ???? ??? ???? ?????. start() ??? ??? run() ??? ??? ???? ????? ?? ?? ??????.

public?class?Test?{
????public?static?void?main(String[]?args)??{
????????System.out.println("主線程ID:"+Thread.currentThread().getId());
????????MyThread?thread1?=?new?MyThread("thread1");
????????thread1.start();
????????MyThread?thread2?=?new?MyThread("thread2");
????????thread2.run();
????}
}
?
?
class?MyThread?extends?Thread{
????private?String?name;
?????
????public?MyThread(String?name){
????????this.name?=?name;
????}
?????
????@Override
????public?void?run()?{
????????System.out.println("name:"+name+"?子線程ID:"+Thread.currentThread().getId());
????}
}

?? ??:

?? ???? ?? ??? ??? ? ????.

1) thread1? thread2 ??? ID? ???, thread2? ?? ???? ??? ID? ????. ?, run ???? ???? ? ???? ???? ?? ?? ????? ?? run ???? ?????.

2) thread1??? thread2? run ????? ?? start ???? ????? thread2? run ??? ??? ??? ??? ?? ????? ? ???? ???? ????? ???? ????. ?? ???? ?? ??? ?????.

2. Runnable ????? ?? Java?? ???? ??? ? Thread ???? ???? ? ??? Runnable ?????? ???? ??? ??? ??? ?? ????. Runnable ?????? ????? ?? run ???? ????? ???.

??? ????.

public?class?Test?{
????public?static?void?main(String[]?args)??{
????????System.out.println("主線程ID："+Thread.currentThread().getId());
????????MyRunnable?runnable?=?new?MyRunnable();
????????Thread?thread?=?new?Thread(runnable);
????????thread.start();
????}
}
?
?
class?MyRunnable?implements?Runnable{
?????
????public?MyRunnable()?{
?????????
????}
?????
????@Override
????public?void?run()?{
????????System.out.println("子線程ID："+Thread.currentThread().getId());
????}
}

Runnable? ??? ??? "??"???. ???? ? ? ??? Runnable ?????? ???? ?? ??? ??? ?? ??? ?? ?? ??? Thread? ????. ? ???? Runnable? Thread ???? ????? ??? ?? Thread? ?? ???? ???? ?? ??? ??? ? ???? ???? ???. Runnable? run ???? ???? ??? ???? ???? ????. ? ???? ??? ??? ??? ??? ????.

??? Thread ???? ?? ?? ??? ???? Thread ???? Runnable ?????? ???? ??? ? ? ????.

Java??? ? ? ?? ??? ???? ?? ??? ???? ???? ?? ? ????. ?? ??? ????? ??? ??? ?? ????. Thread ???? ?? ???? ?? Runnable ?????? ???? ??? ??? ?? ? ??? Java? ?? ??? ????? ??? ?? ???? ?? ???? ???? ?? ?? Runnable ????? ??? ??? ? ????.

3. Callable ? Future? ???? ??? ??? Callable ?????? ??? ?? ???? call() ???? ?????. () ??.

?? ?? ?? ???? ???? ???? ??? ??? ????.

Callable ?????? ?? ???? ???? call() ???? ??? ?? ?? ???? ????? ?????(java8?? ??). , Lambda ???? ???? Callable ??? ?? ??? ? ????.

1. FutureTask ???? ???? Callable ??? call() ???? ?? ?? ????? Callable ??? ?????.
2. FutureTask ??? Thread ??? ???? ???? ???? ???? ?????(FutureTask? ???? ??). Runnable ?????)
3. Call FutureTask ??? get() ???? ?? ??? ?? ? ?? ?? ?? ? ?????.
4. ??? ????.

public?class?Main?{

　　public?static?void?main(String[]?args){

　　　MyThread3?th=new?MyThread3();

　　　//使用Lambda表達式創(chuàng)建Callable對象

　　???//使用FutureTask類來包裝Callable對象

　　　FutureTask<Integer>?future=new?FutureTask<Integer>(

　　　　(Callable<Integer>)()->{

　　　　　　return?5;

　　　　}

　　??);

　　　new?Thread(task,"有返回值的線程").start();//實質(zhì)上還是以Callable對象來創(chuàng)建并啟動線程

　　??try{

　　　　System.out.println("子線程的返回值："+future.get());//get()方法會阻塞，直到子線程執(zhí)行結束才返回

?　　?}catch(Exception?e){

　　　　ex.printStackTrace();

　　　}

　　}

}

? ?? ?? ?? ??? ??: Runnable ? Callable ?????? ???? ?? ??? ?????. ? ??? call() ???? ??? ? ?? ?? ?? ??? run() ???? ??? ? ?? ?? ????. ??? ? ???? ??? ??? ? ????. ? ???? Thread ???? ???? ???? ????.

1. ???? Runnable ?? Callable ?????? ?????. ?? ???? ??????.

2. ?? ???? ?? ???? ?? ??? ??? ? ???, ?? ?? ???? ??? ???? ???? ??? ?? ?????.

3. ??? ?????? ?? ?????. ?? ???? ????? ?? ?? Thread.currentThread() ???? ???? ???.

4. Thread ???? ???? ??? ???? ?? ?? ???? ??? ? ????(Java ?? ?? ??).

PS: ????? ?????? ???? ?? ???? ???? ?? ????

? ??? Java ???? ???? ??? ????. ??? ?????!

? ??? Java?? ???? ???? 3?? ??? ???? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!