Thread

Examples

Java

public interface Runnable {
  void run();
}

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.");
  }
}

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();
    }
  }
}

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.");
  }
}

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();
      }
    }
  }
}

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.");
    }
  }
}

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()

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) {
  }
}

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

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;
  }
}