1.ThreadFactory

Thread工厂,这里自定义的ThreadFactory在创建Thread的时候,执行run方法时移除了TheadLocal

public interface ThreadFactory {
    Thread newThread(Runnable r);
}

public class DefaultThreadFactory implements ThreadFactory {

    private static final AtomicInteger poolId = new AtomicInteger();

    private final AtomicInteger nextId = new AtomicInteger();
    private final String prefix;
    private final boolean daemon;
    private final int priority;
    protected final ThreadGroup threadGroup;

    @Override
    public Thread newThread(Runnable r) {
        Thread t = newThread(new DefaultRunnableDecorator(r), prefix + nextId.incrementAndGet());
        try {
            if (t.isDaemon() != daemon) {
                t.setDaemon(daemon);
            }

            if (t.getPriority() != priority) {
                t.setPriority(priority);
            }
        } catch (Exception ignored) {
            // Doesn't matter even if failed to set.
        }
        return t;
    }

    protected Thread newThread(Runnable r, String name) {
        return new FastThreadLocalThread(threadGroup, r, name);
    }

    private static final class DefaultRunnableDecorator implements Runnable {

        private final Runnable r;

        DefaultRunnableDecorator(Runnable r) {
            this.r = r;
        }

        @Override
        public void run() {
            try {
                r.run();
            } finally {
                FastThreadLocal.removeAll();
            }
        }
    }
}

2.Executor

Executor框架的基础接口

public interface Executor {
    void execute(Runnable command);
}

//每次都使用ThreadFactory创建线程
public final class ThreadPerTaskExecutor implements Executor {
    private final ThreadFactory threadFactory;

    public ThreadPerTaskExecutor(ThreadFactory threadFactory) {
        if (threadFactory == null) {
            throw new NullPointerException("threadFactory");
        }
        this.threadFactory = threadFactory;
    }

    @Override
    public void execute(Runnable command) {
        threadFactory.newThread(command).start();
    }
}

//模拟假线程
public final class ImmediateExecutor implements Executor {
    public static final ImmediateExecutor INSTANCE = new ImmediateExecutor();

    private  ImmediateExecutor() {
        // use static instance
    }

    @Override
    public void execute(Runnable command) {
        if (command == null) {
            throw new NullPointerException("command");
        }
        command.run();
    }
}