水果老虎机游戏


水果老虎机游戏(现在回想一下眼花就几秒种的事,我可是和那个人对视了4,5分钟啊)然后我就哭了起来,期间我还往那边看了几眼,那人慢慢的缩到了谷仓后面不见了。至今我跟好多人说他们都不相信,还有到现在我一直都不敢去看门框。后来我还听我爸爸说了关于我的出生之前的一个有趣而又很不可思议的事,下次再分享给各位。
水果老虎机游戏它见证了我
水果老虎机游戏可惜他们失望了,开的是小,二三四点小,郝仁押下的全都输光了,只有押在二三四点那里赢了。是十二倍哦,算起来,郝仁又是赚了,荷官给郝仁一张一百万元和二张二十万元的筹码。水果老虎机游戏忘不了刚刚过去的那段日子,有着大把的空闲时光,可以任性来读自己喜欢的、不喜欢的各式文章。那一日,禁不住借着百度,找到了一本《当时只道是寻常》;之后的每一天里,一个人反反复复。
水果老虎机游戏花开花落,春去春回。有很多道路,明天等着我们铺陈;有很多棋局,明天等着我们改变;有很多宝藏,明天等着我们开采;有很多困难,明天等着我们克服;有很多考验,明天等着我们挑战;有很多高峰,明天等着我们登攀;有很多版图,明天等着我们描绘;有很多精彩,明天等着我们参与;有很多传奇,明天等着我们缔造。
水果老虎机游戏这是人间的春风,这是生命的源泉。再没有心的沙漠,再没有爱的荒原,死神也望而却步,幸福之花处处开遍!
水果老虎机游戏而接下来的一句话,都让我们大跌眼镜。
水果老虎机游戏我忽然觉得很悲哀,人就是这样善变,或者虚伪。每看到耍猴人的出现,围观的人们总是一边鼓掌一边感叹小猴子真可怜,随后便对着那些耍猴的艺人们越发的苛刻,虐待动物的罪名永远在他们身边围绕。其实只要设身处地的细想,然后会发现,事件之外的人们根本没办法分辨猴子和耍猴子的人谁更可怜的。
水果老虎机游戏小王下午想去参加同学聚会,可不知怎么开口跟科长请假。  我给小王出主意说:“你就说这两天老肚子疼,可能是老毛病阑尾炎犯了,下午得去医院检查一下。”  小王有些心虚:“这样说能行吗?我一点毛病也没有啊!”  我安慰他说:“放心吧,前一阵子科长老犯阑尾炎,才做过手术。他对这病的痛苦有切身体会。”  小王听了,放心地跑去请假了。  工夫不大,小王回来了,很郁闷:“科长一听说我老是阑尾疼,马上就给曾经为他动手术的那个医生打了电话,让我下午过去商量动手术的事……”水果老虎机游戏小陈是个摄影师,每年都给大学生拍毕业照。  这天,他和朋友聊天,朋友问他:“现在大学生照相时,是不是还喊‘茄子’?”  小陈说:“早不喊了,比如今年给理工学院毕业生照相时,那群男生都喊——‘娘子’。”  朋友一听笑了,说:“如果是女生占多数,该不会喊‘汉子’吧?”  小陈连连摇头:“女生多的学院有些喊‘银子’,有些喊‘房子’。”水果老虎机游戏短发护士瞪了他一眼,续道:这不是要命么,最近又是要买车子,我那老公在外面又没挣几个钱,你们瞧瞧,我倒是咋办?我幺儿,你们是不晓得,要喝几百元钱一桶的奶粉?
水果老虎机游戏你出车祸挑的时间不好,因为窗台的风信子淡蓝色的花瓣已经凋谢了,叶子的末端也出现了枯黄,整株花没有了生命力,这花恐怕不能已这样的面目归还给你。
水果老虎机游戏正是。大黑一声大吼,一把掀了桌子,大打出手。挖土机的兄弟们也一拥而上。这个时候,外面忽然杀出几十个黑衣人,头上戴着摩托车头盔,手里挥舞着明晃晃的关公刀。这种刀四五尺长,刀长一尺多,刀柄有丝口,可以安在三尺多长的空心钢管上,出行的时候可以拆下来,携带方便,用的时候接在一起,威力巨大。

皇冠足球比分

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建房子之前先挖地基 - Java BlockingQueue理解

最近一直在看《Think In Java》里关于并发部分的章节,读到第二十一章有一个有趣的比喻:必须先挖房子的地基,但是接下来可以并行的铺设钢结构和构建水泥部件,而这两项任务必须在混凝土浇筑之前完成。管道必须在水泥板浇注之前到位,而水泥板必须在开始构筑房屋骨架之前到位。

在这些任务中,某些可以并行执行,但是某些步骤需要所有的任务都结束之后才能开动,这是线程之间协作的必要性。

在此之前,我们学习过使用notify()、notifyAll()和wait()来控制线程间的协作,让我们先来回顾一下。notify()、notifyAll()和wait()这三个方法同属于Object对象,wait()会使得当前线程等待并交出对象的锁,直到别的线程调用notify()或notifyAll()后可能会被唤醒。

对于一些简单的问题,这已经够用了,但是Java SE5中的concurrent包中提供了BlockingQueue、Condition等类来帮助我们完成更复杂的线程间协作的任务。

下面看一个例子,一台机器具有三个任务:一个制作吐司、一个给吐司抹黄油,另一个在抹过黄油的吐司上涂果酱。通过各个处理过程之间的BlockingQueue来运行这个程序。来自Think In Java (p.s. 我觉得这本书难懂的原因,在于你在理解它教导并发概念的同时,还得十分小心地注意其余的语法细节,一定要有耐心!)。

package concurrency;//: concurrency/ToastOMatic.java
// A toaster that uses queues.
import java.util.concurrent.*;
import java.util.*;
import static net.mindview.utill.Print.*;

class Toast {
  public enum Status { DRY, BUTTERED, JAMMED }
  private Status status = Status.DRY;
  private final int id;
  public Toast(int idn) { id = idn; }
  public void butter() { status = Status.BUTTERED; }
  public void jam() { status = Status.JAMMED; }
  public Status getStatus() { return status; }
  public int getId() { return id; }
  public String toString() {
    return "Toast " + id + ": " + status;
  }
}

class ToastQueue extends LinkedBlockingQueue<Toast> {}

class Toaster implements Runnable {
  private ToastQueue toastQueue;
  private int count = 0;
  private Random rand = new Random(47);
  public Toaster(ToastQueue tq) { toastQueue = tq; }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        TimeUnit.MILLISECONDS.sleep(
          100 + rand.nextInt(500));
        // Make toast
        Toast t = new Toast(count++);
        print(t);
        // Insert into queue
        toastQueue.put(t);
      }
    } catch(InterruptedException e) {
      print("Toaster interrupted");
    }
    print("Toaster off");
  }
}

// Apply butter to toast:
class Butterer implements Runnable {
  private ToastQueue dryQueue, butteredQueue;
  public Butterer(ToastQueue dry, ToastQueue buttered) {
    dryQueue = dry;
    butteredQueue = buttered;
  }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        // Blocks until next piece of toast is available:
        Toast t = dryQueue.take();
        t.butter();
        print(t);
        butteredQueue.put(t);
      }
    } catch(InterruptedException e) {
      print("Butterer interrupted");
    }
    print("Butterer off");
  }
}

// Apply jam to buttered toast:
class Jammer implements Runnable {
  private ToastQueue butteredQueue, finishedQueue;
  public Jammer(ToastQueue buttered, ToastQueue finished) {
    butteredQueue = buttered;
    finishedQueue = finished;
  }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        // Blocks until next piece of toast is available:
        Toast t = butteredQueue.take();
        t.jam();
        print(t);
        finishedQueue.put(t);
      }
    } catch(InterruptedException e) {
      print("Jammer interrupted");
    }
    print("Jammer off");
  }
}

// Consume the toast:
class Eater implements Runnable {
  private ToastQueue finishedQueue;
  private int counter = 0;
  public Eater(ToastQueue finished) {
    finishedQueue = finished;
  }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        // Blocks until next piece of toast is available:
        Toast t = finishedQueue.take();
        // Verify that the toast is coming in order,
        // and that all pieces are getting jammed:
        if(t.getId() != counter++ ||
           t.getStatus() != Toast.Status.JAMMED) {
          print(">>>> Error: " + t);
          System.exit(1);
        } else
          print("Chomp! " + t);
      }
    } catch(InterruptedException e) {
      print("Eater interrupted");
    }
    print("Eater off");
  }
}

public class ToastOMatic {
  public static void main(String[] args) throws Exception {
    ToastQueue dryQueue = new ToastQueue(),
               butteredQueue = new ToastQueue(),
               finishedQueue = new ToastQueue();
    ExecutorService exec = Executors.newCachedThreadPool();
    exec.execute(new Toaster(dryQueue));
    exec.execute(new Butterer(dryQueue, butteredQueue));
    exec.execute(new Jammer(butteredQueue, finishedQueue));
    exec.execute(new Eater(finishedQueue));
    TimeUnit.SECONDS.sleep(5);
    exec.shutdownNow();
  }
} /* (Execute to see output) *///:~
View Code

看完晕乎乎的?很正常,所以才需要我来给大家讲解啦 :)

首先可以注意到的,程序中并没有出现任何Lock对象或是synchronized关键字来同步,这是因为在实现BlockingQueue的队列类内部已经使用Condition在维护。这降低了程序的耦合度,使得每个类只需要和自己的BlockingQueue通信。

程序中定义了:

一个实体类:Toast。使用enum来管理状态是一个优秀的示例。

三个队列:dryQueue、butteredQueue、finishedQueue

四个Runnable任务:Toaster、Butterer、Jammer、Eater

根据字面意思理解,当线程不被中断的时候,Toaster负责制作吐司,所以只需要和dryQueue通信。Butterer在吐司上涂黄油,需要从dryQueue中取出原味土司,涂上黄油(t.butter())后放入butteredQueue。Jammer在抹过黄油的吐司上涂果酱,需要从butteredQueue中取出,涂上果酱后放入finishedQueue。Eater就只需要从finishedQueue中取出来吃啦。细心的读者还会发现Eater中做了检查,如果不是涂上果酱的吐司就不吃(傲娇的表情)。如果线程被中断,任务就打印信息并退出。

TimeUnit.SECONDS.sleep(3)的作用是当前线程等待3秒,等待后台制作吐司。exec.shutdownNow()停止当前线程池。

 

是不是觉得自己理解了?那么还有一道课后题留给大家:修改ToastOMatic.java,使用两个单独的组装线来创建涂有黄油和果酱的三明治(即不必先涂黄油再涂果酱,可以异步处理,明显提高工作效率)。

答案在这里:

//: concurrency/E29_ToastOMatic2.java
/********************** Exercise 29 ***********************
 * Modify ToastOMatic.java to create peanut butter and jelly
 * on toast sandwiches using two separate assembly lines 
 * (one for peanut butter, the second for jelly, then
 * merging the two lines).
*********************************************************/
package concurrency;
import java.util.concurrent.*;
import java.util.*;
import static net.mindview.utill.Print.*;

class Toast {
  public enum Status { 
    DRY,
    BUTTERED,
    JAMMED,
    READY {
      public String toString() {
        return
          BUTTERED.toString() + " & " + JAMMED.toString();
      }
    }
  }
  private Status status = Status.DRY;
  private final int id;
  public Toast(int idn) { id = idn; }
  public void butter() {
    status =
      (status == Status.DRY) ? Status.BUTTERED :
                               Status.READY;
  }
  public void jam() {
    status =
      (status == Status.DRY) ? Status.JAMMED :
                               Status.READY;
  }
  public Status getStatus() { return status; }
  public int getId() { return id; }
  public String toString() {
    return "Toast " + id + ": " + status;
  }
}

class ToastQueue extends LinkedBlockingQueue<Toast> {}

class Toaster implements Runnable {
  private ToastQueue toastQueue;
  private int count;
  private Random rand = new Random(47);
  public Toaster(ToastQueue tq) { toastQueue = tq; }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        TimeUnit.MILLISECONDS.sleep(
          100 + rand.nextInt(500));
        // Make toast
        Toast t = new Toast(count++);
        print(t);
        // Insert into queue
        toastQueue.put(t);
      }
    } catch(InterruptedException e) {
      print("Toaster interrupted");
    }
    print("Toaster off");
  }
}

// Apply butter to toast:
class Butterer implements Runnable {
  private ToastQueue inQueue, butteredQueue;
  public Butterer(ToastQueue in, ToastQueue buttered) {
    inQueue = in;
    butteredQueue = buttered;
  }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        // Blocks until next piece of toast is available:
        Toast t = inQueue.take();
        t.butter();
        print(t);
        butteredQueue.put(t);
      }
    } catch(InterruptedException e) {
      print("Butterer interrupted");
    }
    print("Butterer off");
  }
}

// Apply jam to toast:
class Jammer implements Runnable {
  private ToastQueue inQueue, jammedQueue;
  public Jammer(ToastQueue in, ToastQueue jammed) {
    inQueue = in;
    jammedQueue = jammed;
  }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        // Blocks until next piece of toast is available:
        Toast t = inQueue.take();
        t.jam();
        print(t);
        jammedQueue.put(t);
      }
    } catch(InterruptedException e) {
      print("Jammer interrupted");
    }
    print("Jammer off");
  }
}

// Consume the toast:
class Eater implements Runnable {
  private ToastQueue finishedQueue;
  public Eater(ToastQueue finished) {
    finishedQueue = finished;
  }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        // Blocks until next piece of toast is available:
        Toast t = finishedQueue.take();
        // Verify that all pieces are ready for consumption:
        if(t.getStatus() != Toast.Status.READY) {
          print(">>>> Error: " + t);
          System.exit(1);
        } else
          print("Chomp! " + t);
      }
    } catch(InterruptedException e) {
      print("Eater interrupted");
    }
    print("Eater off");
  }
}

// Outputs alternate inputs on alternate channels:
class Alternator implements Runnable {
  private ToastQueue inQueue, out1Queue, out2Queue;
  private boolean outTo2;  // control alternation
  public Alternator(ToastQueue in, ToastQueue out1,
          ToastQueue out2) {
    inQueue = in;
    out1Queue = out1;
    out2Queue = out2;
  }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        // Blocks until next piece of toast is available:
        Toast t = inQueue.take();
        if(!outTo2)
          out1Queue.put(t);
        else
          out2Queue.put(t);
        outTo2 = !outTo2;  // change state for next time
      }
    } catch(InterruptedException e) {
      print("Alternator interrupted");
    }
    print("Alternator off");
  }
}

// Accepts toasts on either channel, and relays them on to
// a "single" successor
class Merger implements Runnable {
  private ToastQueue in1Queue, in2Queue, toBeButteredQueue,
    toBeJammedQueue, finishedQueue;
  public Merger(ToastQueue in1, ToastQueue in2,
          ToastQueue toBeButtered, ToastQueue toBeJammed,
          ToastQueue finished) {
    in1Queue = in1;
    in2Queue = in2;
    toBeButteredQueue = toBeButtered;
    toBeJammedQueue = toBeJammed;
    finishedQueue = finished;
  }
  public void run() {
    try {
      while(!Thread.interrupted()) {
        // Blocks until next piece of toast is available:
        Toast t = null;
        while(t == null) {
          t = in1Queue.poll(50, TimeUnit.MILLISECONDS);
          if(t != null)
            break;
          t = in2Queue.poll(50, TimeUnit.MILLISECONDS);
        }
        // Relay toast onto the proper queue
        switch(t.getStatus()) {
          case BUTTERED:
            toBeJammedQueue.put(t);
            break;
          case JAMMED:
            toBeButteredQueue.put(t);
            break;
          default:
            finishedQueue.put(t);
        }
      }
    } catch(InterruptedException e) {
      print("Merger interrupted");
    }
    print("Merger off");
  }
}

public class E29_ToastOMatic2 {
  public static void main(String[] args) throws Exception {
    ToastQueue 
      dryQueue = new ToastQueue(),
      butteredQueue = new ToastQueue(),
      toBeButteredQueue = new ToastQueue(),
      jammedQueue = new ToastQueue(),
      toBeJammedQueue = new ToastQueue(),
      finishedQueue = new ToastQueue();
    ExecutorService exec = Executors.newCachedThreadPool();
    exec.execute(new Toaster(dryQueue));
    exec.execute(new Alternator(dryQueue, toBeButteredQueue,
      toBeJammedQueue));
    exec.execute(
      new Butterer(toBeButteredQueue, butteredQueue));
    exec.execute(
      new Jammer(toBeJammedQueue, jammedQueue));
    exec.execute(new Merger(butteredQueue , jammedQueue,
      toBeButteredQueue, toBeJammedQueue, finishedQueue));
    exec.execute(new Eater(finishedQueue));
    TimeUnit.SECONDS.sleep(5);
    exec.shutdownNow();
  }
} /* (Execute to see output) *///:~
没想清楚前不许偷看!

因为代码比较长,推荐把代码导入IDE查看。

 

posted on 2015-11-24 16:40 andrew-chen 阅读(...) 评论(...) 编辑 收藏

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