======
Thread
======

--------
Examples
--------

Java
====

.. code-block:: java

  public interface Runnable {
    void run();
  }

.. code-block:: java

  public class RunnableThreadExample implements Runnable {
    public int count = 0;

    public void run() {
      System.out.println("RunnableThread starting.");
      try {
        while (count < 5) {
          Thread.sleep(500);
          count++;
        }
      } catch (InterruptedException exc) {
        System.out.println("RunnableThread interrupted.");
      }
      System.out.println("RunnableThread terminating.");
    }
  }

.. code-block:: java

  public static void main(String[] args) {
    RunnableThreadExample instance = new RunnableThreadExample();
    Thread thread = new Thread(instance);
    thread.start();

    while (instance.count != 5) {
      try {
        Thread.sleep(250);
      } catch (InterruptedException exc) {
        exc.printStackTrace();
      }
    }
  }

.. code-block:: java

  public class ThreadExample extends Thread {
    int count = 0;

    public void run() {
      System.out.println("Thread starting.");
      try {
        while (count < 5) {
          Thread.sleep(500);
          System.out.println("In Thread, count is " + count);
          count++;
        }
      } catch (InterruptedException exc) {
        System.out.println("Thread interrupted.");
      }
      System.out.println("Thread terminating.");
    }
  }

.. code-block:: java

  public class ExampleB {
    public static void main(String args[]) {
      ThreadExample instance = new ThreadExample();
      instance.start();

      while (instance.count != 5) {
        try {
          Thread.sleep(250);
        } catch (InterruptedException exc) {
          exc.printStackTrace();
        }
      }
    }
  }

.. code-block:: java

  public class MyClass extends Thread {
    private String name;
    private MyObject myObj;

    public MyClass(MyObject obj, String n) {
      name = n;
      myObj = obj;
    }

    public void run() {
      myObj.foo(name);
    }
  }

  public class MyObject {
    public synchronized void foo(String name) {
      try {
        System.out.println("Thread " + name + ".foo(): starting");
        Thread.sleep(3000);
        System.out.println("Thread " + name + ".foo(): ending");
      } catch (InterruptedException exc) {
        System.out.println("Thread " + name + ": interrupted.");
      }
    }
  }

.. code-block:: java

  MyObject obj1 = new MyObject();
  MyObject obj2 = new MyObject();
  MyClass thread1 = new MyClass(obj1, "1");
  MyClass thread2 = new MyClass(obj2, "2");
  thread1.start();
  thread2.start();

  MyObject obj = new MyObject();
  MyClass thread 1 = new MyClass(obj, "1");
  MyClass thread 2 = new MyClass(obj, "2");
  thread1.start()
  thread2.start()

.. code-block:: java

  public class MyClass extends Thread {
    ...
    public void run() {
      if (name.equals("1")) MyObject.foo(name);
      else if (name.equals("2")) MyObject.bar(name);
    }
  }

  public class MyObject {
    public static synchronized void foo(String name) {
    }
    public static synchronized void bar(String name) {
    }
  }

.. code-block:: java

  public class MyClass extends Thread {
    ...
    public void run() {
      myObj.foo(name);
    }
  }
  public class MyObject {
    public void foo(String name) {
      synchronized(this) {
        ...
      }
    }
  }

.. code-block:: java

  public class LockedATM {
    private Lock lock;
    private int balance = 100;

    public LockedATM() {
      lock = new ReentrantLock();
    }

    public int withdraw(int value) {
      lock.lock();
      int temp = balance;
      try {
        Thread.sleep(100);
        temp = temp - value;
        Thread.sleep(100);
        balance = temp;
      } catch (InterruptedException e) { }
      lock.unlock();
      return temp;
    }

    public int deposit(int value) {
      lock.lock();
      int temp = balance;
      try {
        Thread.sleep(100);
        temp = temp + value;
        Thread.sleep(300);
        balance = temp;
      } catch (InterruptedException e) { }
      lock.unlock();
      return temp;
    }
  }