java 并发编程(2)

java_thread

本来想都以做菜开饭来讲解这个套 java 并发编程，不过对于那些不做菜的朋友有点太乏味了，也缺乏亲身体验，所以还是多元化，关键是以做菜为例进行讲解在配上美食图，会不会听到不是知识饥渴，而真的变得饥渴了。

starcraft barracks

这个游戏是我的时代游戏，一听就能猜出我大概哪个时代的人了? 也不一定。游戏过程中我们获取资源，用资源建造兵营，兵营负责出兵进行战斗。

兵营的任务就是建造士兵，所以可以将线程比喻成兵营，代码如下。

• 玩过游戏的人都知道兵数量是有上限的，这里给 50.
• 而且兵是一个一个出。

public class Barracks extends Thread{

    private final String name;

    private final int MAX = 50;
    private int index = 1;

    public Barracks(String name) {
        this.name = name;
    }

    @Override
    public void run() {
        while(index <= MAX){
            System.out.println("barrack  " + name + " create warrior: " + (index++));
        }
    }
}

public class ClientB {

    public static void main(String[] args) {
        Barracks barracks = new Barracks("one");
        barracks.start();
    }

}

为了快速出兵，我们可以建造多个兵营同时出兵。

    public static void main(String[] args) {
        Barracks barrackOne = new Barracks("one");
        barrackOne.start();

        Barracks barrackTwo = new Barracks("two");
        barrackTwo.start();

        Barracks barrackThree = new Barracks("three");
        barrackThree.start();
    }

不过从输出来看，因为出兵数量控制业务逻辑放置兵营（线程），这样就带来问题。对兵数量控制应该交个种族而不是兵营

barrack  two create warrior: 2
barrack  three create warrior: 3
barrack  one create warrior: 1
barrack  three create warrior: 5
barrack  two create warrior: 4
barrack  three create warrior: 7
barrack  one create warrior: 6
barrack  three create warrior: 9
barrack  two create warrior: 8
barrack  three create warrior: 11
barrack  one create warrior: 10
barrack  three create warrior: 13
barrack  two create warrior: 12
barrack  three create warrior: 15
barrack  one create warrior: 14
barrack  three create warrior: 17
barrack  two create warrior: 16
barrack  two create warrior: 20
barrack  two create warrior: 21
barrack  three create warrior: 19
barrack  one create warrior: 18
barrack  three create warrior: 23
barrack  three create warrior: 25
barrack  two create warrior: 22
barrack  three create warrior: 26
barrack  one create warrior: 24
barrack  three create warrior: 28
barrack  two create warrior: 27
barrack  three create warrior: 30
barrack  one create warrior: 29
barrack  three create warrior: 32
barrack  two create warrior: 31
barrack  three create warrior: 34
barrack  three create warrior: 36
barrack  one create warrior: 33
barrack  one create warrior: 38
barrack  three create warrior: 37
barrack  three create warrior: 40
barrack  three create warrior: 41
barrack  two create warrior: 35
barrack  three create warrior: 42
barrack  one create warrior: 39
barrack  three create warrior: 44
barrack  two create warrior: 43
barrack  three create warrior: 46
barrack  one create warrior: 45
barrack  one create warrior: 49
barrack  one create warrior: 50
barrack  three create warrior: 48
barrack  two create warrior: 47

我们可以把这些业务逻辑冲一个个线程从提取到 Runnable 接口以达到多线程共享。

public class BarrackRunnable implements Runnable{

    private int index = 0;
    private final static int MAX = 50;


    @Override
    public void run() {
        while(index <= MAX){
            System.out.println("barrack  " + Thread.currentThread().getName() + " create warrior: " + (index++));
        }
    }
}

public class ClientC {

    public static void main(String[] args) {
        final BarrackRunnable barrackRunnable = new BarrackRunnable();

        Thread barrackThreadOne = new Thread(barrackRunnable,"one");
        Thread barrackThreadTwo = new Thread(barrackRunnable,"two");
        Thread barrackThreadThree = new Thread(barrackRunnable,"three");

        barrackThreadOne.start();
        barrackThreadTwo.start();
        barrackThreadThree.start();

    }
}

barrack  one create warrior: 0
barrack  one create warrior: 3
barrack  one create warrior: 4
barrack  one create warrior: 5
barrack  one create warrior: 6
barrack  one create warrior: 7
barrack  one create warrior: 8
barrack  one create warrior: 9
barrack  one create warrior: 10
barrack  one create warrior: 11
barrack  one create warrior: 12
barrack  one create warrior: 13
barrack  one create warrior: 14
barrack  one create warrior: 15
barrack  one create warrior: 16
barrack  one create warrior: 17
barrack  one create warrior: 18
barrack  two create warrior: 1
barrack  two create warrior: 20
barrack  two create warrior: 21
barrack  two create warrior: 22
barrack  one create warrior: 19
barrack  one create warrior: 24
barrack  one create warrior: 25
barrack  one create warrior: 26
barrack  one create warrior: 27
barrack  one create warrior: 28
barrack  one create warrior: 29
barrack  one create warrior: 30
barrack  one create warrior: 31
barrack  two create warrior: 23
barrack  two create warrior: 33
barrack  two create warrior: 34
barrack  one create warrior: 32
barrack  one create warrior: 36
barrack  two create warrior: 35
barrack  two create warrior: 38
barrack  two create warrior: 39
barrack  one create warrior: 37
barrack  one create warrior: 41
barrack  two create warrior: 40
barrack  two create warrior: 43
barrack  one create warrior: 42
barrack  one create warrior: 45
barrack  one create warrior: 46
barrack  one create warrior: 47
barrack  one create warrior: 48
barrack  one create warrior: 49
barrack  one create warrior: 50
barrack  two create warrior: 44
barrack  three create warrior: 2

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