/**

 *  守護(hù)線(xiàn)程

 */

public class Daemons {

 

    /**

     * @param args

     * @throws InterruptedException

     */

    public static void main(String[] args) throws InterruptedException {

        Thread d = new Thread(new Daemon());

        d.setDaemon(true); //必須在啟動(dòng)線(xiàn)程前調(diào)用

        d.start();

        System.out.println("d.isDaemon() = " + d.isDaemon() + ".");

        TimeUnit.SECONDS.sleep(1);

    }

 

}

 

class DaemonSpawn implements Runnable {

 

    public void run() {

        while (true) {

            Thread.yield();

        }

    }

   

}

 

class Daemon implements Runnable {

    private Thread[] t = new Thread[10];

 

    public void run() {

        for (int i=0; i<t.length; i++) {

            t[i] = new Thread(new DaemonSpawn());

            t[i].start();

            System.out.println("DaemonSpawn " + i + " started.");

        }

        for (int i=0; i<t.length; i++) {

            System.out.println("t[" + i + "].isDaemon() = " +

                    t[i].isDaemon() + ".");

        }

        while (true) {

            Thread.yield();

        }

    }

   

}

 

運(yùn)行結(jié)果：

d.isDaemon() = true.
DaemonSpawn 0 started.
DaemonSpawn 1 started.
DaemonSpawn 2 started.
DaemonSpawn 3 started.
DaemonSpawn 4 started.
DaemonSpawn 5 started.
DaemonSpawn 6 started.
DaemonSpawn 7 started.
DaemonSpawn 8 started.
DaemonSpawn 9 started.
t[0].isDaemon() = true.
t[1].isDaemon() = true.
t[2].isDaemon() = true.
t[3].isDaemon() = true.
t[4].isDaemon() = true.
t[5].isDaemon() = true.
t[6].isDaemon() = true.
t[7].isDaemon() = true.
t[8].isDaemon() = true.
t[9].isDaemon() = true.

在第二版的664頁(yè)，其中我看到這兩個(gè)while() yield()（使任務(wù)一直處于讓出線(xiàn)程的狀態(tài)）;
一直讓出線(xiàn)程？這有什么意義呢？比如DaemonSpawn，這個(gè)任務(wù) 你讓他平平靜靜的執(zhí)行完不就好了嗎？執(zhí)行完
就解放線(xiàn)程了。Daemon中的while() yield(); 又有什么意義呢？main本來(lái)就只啟動(dòng)了一個(gè)線(xiàn)程來(lái)執(zhí)行Daemon任務(wù)
那讓他平平靜靜執(zhí)行完不就好了嗎。。。。。。。對(duì)角懵逼，線(xiàn)性懵逼啊

誰(shuí)能系統(tǒng)的解釋一下嗎？？？？
ps：最近在學(xué)線(xiàn)程，各位有什么方法，書(shū)籍，途徑 介紹嗎？看think in java看的好吃力