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/*
* Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
* All rights reserved. Software written by Ian F. Darwin and others.
* $Id: ProdCons1.java,v 1.5 2004/02/09 03:34:07 ian Exp $
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    do*****entation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*        This product includes software developed by Ian F. Darwin.
* 4. Neither the name of the author nor the names of its
*    contributors may be used to endorse or promote products derived
*    from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
* cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
* pioneering role in inventing and promulgating (and standardizing) the Java
* language and environment is gratefully acknowledged.
*
* The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
* inventing predecessor languages C and C++ is also gratefully acknowledged.
*/

import java.util.*;
import java.io.*;

/** Producer-Consumer in Java. Version 1.
*/
public class ProdCons1 {

  protected LinkedList list = new LinkedList();

  protected void produce() {
    int len = 0;
    synchronized(list) {
      Object justProduced = new Object();
      list.addFirst(justProduced);
      len = list.size();
      list.notifyAll();
    }
    System.out.println("List size now " + len);
  }

  protected void consume() {
    Object obj = null;
    int len = 0;
    synchronized(list) {
      while (list.size() == 0) {
        try {
          list.wait();
        } catch (InterruptedException ex) {
          return;
        }
      }
      obj = list.removeLast();
      len = list.size();
    }
    System.out.println("Consuming object " + obj);
    System.out.println("List size now " + len);
  }

  public static void main(String[] args) throws IOException {
    ProdCons1 pc = new ProdCons1();
    System.out.println("Ready (p to produce, c to consume):");
    int i;
    while ((i = System.in.read()) != -1) {
      char ch = (char)i;
      switch(ch) {
        case 'p':  pc.produce(); break;
        case 'c':  pc.consume(); break;
      }
    }
  }
}

/**
* Java Code from Java Cookbook, Second Edition
* By Ian F. Darwin
* Second Edition June 2004
* Series: Cookbooks
* ISBN: 0-596-00701-9
* Details: http://www.oreilly.com/catalog/javacook2/index.html
* Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
* All rights reserved. Software written by Ian F. Darwin and others.
* $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
*/

/*
* Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
* All rights reserved. Software written by Ian F. Darwin and others.
* $Id: ProdCons2.java,v 1.9 2004/02/09 03:34:07 ian Exp $
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    do*****entation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*        This product includes software developed by Ian F. Darwin.
* 4. Neither the name of the author nor the names of its
*    contributors may be used to endorse or promote products derived
*    from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
* cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
* pioneering role in inventing and promulgating (and standardizing) the Java
* language and environment is gratefully acknowledged.
*
* The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
* inventing predecessor languages C and C++ is also gratefully acknowledged.
*/

import java.util.*;
import java.io.*;

/** Producer-consumer in Java, Take II.
*/
public class ProdCons2 {

  /** Throughout the code, this is the object we synchronize on so this
   * is also the object we wait() and notifyAll() on.
   */
  protected LinkedList list = new LinkedList();
  protected int MAX = 10;
  protected boolean done = false; // Also protected by lock on list.

  /** Inner class representing the Producer side */
  class Producer extends Thread {

    public void run() {
      while (true) {
        Object justProduced = getRequestFromNetwork();
        // Get request from the network - outside the synch section.
        // We're simulating this actually reading from a client, and it
        // might have to wait for hours if the client is having coffee.
        synchronized(list) {
            while (list.size() == MAX) // queue "full"
            try {
              System.out.println("Producer WAITING");
              list.wait();   // Limit the size
            } catch (InterruptedException ex) {
              System.out.println("Producer INTERRUPTED");
            }
          list.addFirst(justProduced);
          list.notifyAll();  // must own the lock
          System.out.println("Produced 1; List size now " + list.size());
          if (done)
            break;
          // yield();  // Useful for green threads & demo programs.
        }
      }
    }

    Object getRequestFromNetwork() {  // Simulation of reading from client
      // try {
      //   Thread.sleep(10); // simulate time passing during read
      // } catch (InterruptedException ex) {
      //   System.out.println("Producer Read INTERRUPTED");
      // }
      return(new Object());
    }
  }

  /** Inner class representing the Consumer side */
  class Consumer extends Thread {
    public void run() {
      while (true) {
        Object obj = null;
        synchronized(list) {
          while (list.size() == 0) {
            try {
              System.out.println("CONSUMER WAITING");
              list.wait();  // must own the lock
            } catch (InterruptedException ex) {
              System.out.println("CONSUMER INTERRUPTED");
            }
          }
          obj = list.removeLast();
          list.notifyAll();
          int len = list.size();
          System.out.println("List size now " + len);
          if (done)
            break;
        }
        process(obj);  // Outside synch section (could take time)
        //yield(); DITTO
      }
    }

    void process(Object obj) {
      // Thread.sleep(xxx) // Simulate time passing
      System.out.println("Consuming object " + obj);
    }
  }

  ProdCons2(int nP, int nC) {
    for (int i=0; i<nP; i++)
      new Producer().start();
    for (int i=0; i<nC; i++)
      new Consumer().start();
  }

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

    // Start producers and consumers
    int numProducers = 4;
    int numConsumers = 3;
    ProdCons2 pc = new ProdCons2(numProducers, numConsumers);

    // Let it run for, say, 10 seconds
    Thread.sleep(10*1000);

    // End of simulation - shut down gracefully
    synchronized(pc.list) {
      pc.done = true;
      pc.list.notifyAll();
    }
  }
}

import java.util.*;
import java.io.*;
import java.util.concurrent.*;

/** Producer-Consumer in Java, for J2SE 1.5 using concurrent.
*/
public class ProdCons15 {

  protected boolean done = false;

  /** Inner class representing the Producer side */
  class Producer implements Runnable {

    protected BlockingQueue queue;

    Producer(BlockingQueue theQueue) { this.queue = theQueue; }

    public void run() {
      try {
        while (true) {
          Object justProduced = getRequestFromNetwork();
          queue.put(justProduced);
          System.out.println("Produced 1 object; List size now " + queue.size());
          if (done) {
            return;
          }
        }
      } catch (InterruptedException ex) {
        System.out.println("Producer INTERRUPTED");
      }
    }

    Object getRequestFromNetwork() {  // Simulation of reading from client
      try {
          Thread.sleep(10); // simulate time passing during read
      } catch (InterruptedException ex) {
         System.out.println("Producer Read INTERRUPTED");
      }
      return(new Object());
    }
  }

  /** Inner class representing the Consumer side */
  class Consumer implements Runnable {
    protected BlockingQueue queue;

    Consumer(BlockingQueue theQueue) { this.queue = theQueue; }

    public void run() {
      try {
        while (true) {
          Object obj = queue.take();
          int len = queue.size();
          System.out.println("List size now " + len);
          process(obj);
          if (done) {
            return;
          }
        }
      } catch (InterruptedException ex) {
          System.out.println("CONSUMER INTERRUPTED");
      }
    }

    void process(Object obj) {
      // Thread.sleep(xxx) // Simulate time passing
      System.out.println("Consuming object " + obj);
    }
  }

  ProdCons15(int nP, int nC) {
    BlockingQueue myQueue = new LinkedBlockingQueue();
    for (int i=0; i<nP; i++)
      new Thread(new Producer(myQueue)).start();
    for (int i=0; i<nC; i++)
      new Thread(new Consumer(myQueue)).start();
  }

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

    // Start producers and consumers
    int numProducers = 4;
    int numConsumers = 3;
    ProdCons15 pc = new ProdCons15(numProducers, numConsumers);

    // Let the simulation run for, say, 10 seconds
    Thread.sleep(10*1000);

    // End of simulation - shut down gracefully
    pc.done = true;
  }
}