OnJava8-Examples/tasks/ThreadVariations.java

// tasks/ThreadVariations.java
// (c)2016 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
// Creating threads with inner classes
import java.util.concurrent.*;

// Using a named inner class:
class InnerThread1 {
  private int countDown = 5;
  private Inner inner;
  private class Inner extends Thread {
    Inner(String name) {
      super(name);
      start();
    }
    @Override
    public void run() {
      try {
        while(true) {
          System.out.println(this);
          if(--countDown == 0) return;
          sleep(10);
        }
      } catch(InterruptedException e) {
        System.out.println("interrupted");
      }
    }
    @Override
    public String toString() {
      return getName() + ": " + countDown;
    }
  }
  public InnerThread1(String name) {
    inner = new Inner(name);
  }
}

// Using an anonymous inner class:
class InnerThread2 {
  private int countDown = 5;
  private Thread t;
  public InnerThread2(String name) {
    t = new Thread(name) {
      @Override
      public void run() {
        try {
          while(true) {
            System.out.println(this);
            if(--countDown == 0) return;
            sleep(10);
          }
        } catch(InterruptedException e) {
          System.out.println("sleep() interrupted");
        }
      }
      @Override
      public String toString() {
        return getName() + ": " + countDown;
      }
    };
    t.start();
  }
}

// Using a named Runnable implementation:
class InnerRunnable1 {
  private int countDown = 5;
  private Inner inner;
  private class Inner implements Runnable {
    Thread t;
    Inner(String name) {
      t = new Thread(this, name);
      t.start();
    }
    @Override
    public void run() {
      try {
        while(true) {
          System.out.println(this);
          if(--countDown == 0) return;
          TimeUnit.MILLISECONDS.sleep(10);
        }
      } catch(InterruptedException e) {
        System.out.println("sleep() interrupted");
      }
    }
    @Override
    public String toString() {
      return t.getName() + ": " + countDown;
    }
  }
  public InnerRunnable1(String name) {
    inner = new Inner(name);
  }
}

// Using an anonymous Runnable implementation:
class InnerRunnable2 {
  private int countDown = 5;
  private Thread t;
  public InnerRunnable2(String name) {
    t = new Thread(new Runnable() {
      @Override
      public void run() {
        try {
          while(true) {
            System.out.println(this);
            if(--countDown == 0) return;
            TimeUnit.MILLISECONDS.sleep(10);
          }
        } catch(InterruptedException e) {
          System.out.println("sleep() interrupted");
        }
      }
      @Override
      public String toString() {
        return Thread.currentThread().getName() +
          ": " + countDown;
      }
    }, name);
    t.start();
  }
}

// A separate method to run some code as a task:
class ThreadMethod {
  private int countDown = 5;
  private Thread t;
  private String name;
  public ThreadMethod(String name) { this.name = name; }
  public void runTask() {
    if(t == null) {
      t = new Thread(name) {
        @Override
        public void run() {
          try {
            while(true) {
              System.out.println(this);
              if(--countDown == 0) return;
              sleep(10);
            }
          } catch(InterruptedException e) {
            System.out.println("sleep() interrupted");
          }
        }
        @Override
        public String toString() {
          return getName() + ": " + countDown;
        }
      };
      t.start();
    }
  }
}

public class ThreadVariations {
  public static void main(String[] args) {
    new InnerThread1("InnerThread1");
    new InnerThread2("InnerThread2");
    new InnerRunnable1("InnerRunnable1");
    new InnerRunnable2("InnerRunnable2");
    new ThreadMethod("ThreadMethod").runTask();
  }
}
/* Output:
InnerThread1: 5
InnerThread2: 5
InnerThread1: 4
InnerThread2: 4
InnerThread1: 3
InnerThread2: 3
InnerThread1: 2
InnerThread2: 2
InnerRunnable1: 5
InnerThread1: 1
InnerThread2: 1
InnerRunnable2: 5
InnerRunnable1: 4
InnerRunnable2: 4
InnerRunnable1: 3
InnerRunnable2: 3
InnerRunnable1: 2
InnerRunnable2: 2
InnerRunnable1: 1
InnerRunnable2: 1
ThreadMethod: 5
ThreadMethod: 4
ThreadMethod: 3
ThreadMethod: 2
ThreadMethod: 1
*/