ThreadFactory类的使用

　　之前创建线程的话，基本上是使用new Thread()，或者是将任务提交到线程池执行。今天看了一下洁城浩的《图解java多线程设计模式》突然看到还可以使用ThreadFactory来创建一个线程，感觉挺新奇的，就写了一个Example类来跑一下 。

 public class ThreadFactoryExample {
     public static void main(String[] args) {
         ThreadFactory factory = Executors.defaultThreadFactory();
         factory.newThread(new Task()).start();
         for (int i = 0; i < 10; i++) {
             System.out.println("Hello");
         }
     }
 }

 class Task implements Runnable {

     @Override
     public void run() {
         for (int i = 0; i < 10; i++) {
             System.out.println("Task");
         }
     }
 }

　　挺简单的使用方式。看了一下，Executors工具类返回的是DefaultThreadFactory类的实例，这个类的是一个Executors的内部类，代码很少，如下

 static class DefaultThreadFactory implements ThreadFactory {
         private static final AtomicInteger poolNumber = new AtomicInteger(1);
         private final ThreadGroup group;
         private final AtomicInteger threadNumber = new AtomicInteger(1);
         private final String namePrefix;

         DefaultThreadFactory() {
             SecurityManager s = System.getSecurityManager();
             group = (s != null) ? s.getThreadGroup() :
                                   Thread.currentThread().getThreadGroup();
             namePrefix = "pool-" +
                           poolNumber.getAndIncrement() +
                          "-thread-";
         }

         public Thread newThread(Runnable r) {
             Thread t = new Thread(group, r,
                                   namePrefix + threadNumber.getAndIncrement(),
                                   0);
             if (t.isDaemon())
                 t.setDaemon(false);
             if (t.getPriority() != Thread.NORM_PRIORITY)
                 t.setPriority(Thread.NORM_PRIORITY);
             return t;
         }
     }