package devmanuals.com;

import java.util.concurrent.BlockingDeque;
import java.util.concurrent.LinkedBlockingDeque;

class Peek implements Runnable {
	BlockingDeque<Integer> bdq;

	public Peek(BlockingDeque<Integer> bdq) {
		this.bdq = bdq;
	}

	public void run() {
		System.out.println("Elements of deque are : ");
		int i;
		boolean bol = false;
		for (i = 0; i < 5; i++) {
				bdq.add(i);
			}
			System.out.println(bdq);
			System.out.println("Size of deque = " + bdq.size());
		try {
			Thread.sleep(500);
			System.out.println("The first element of deque is = ");
			Thread.sleep(1000);
			Integer obj = bdq.peek();
			System.out.println(obj);
			bol = bdq.contains(obj);
			System.out.println("The element " + obj
					+ " is still present into the deque? ");
			Thread.sleep(1000);
			System.out.println(bol);
			System.out.println("Now removed all the elements from the deque");
			bdq.clear();
			System.out.println("Therefore the deque is "+bdq+" empty");
			System.out.println("Therefore first element of deque is : ");
			Integer obj1= bdq.peek();//call of this method will return 'null'
			Thread.sleep(2000);
			System.out.println(obj1);
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
	}
		
}

public class BdqPeek {
	public static void main(String[] args) {
		BlockingDeque<Integer> bdq = new LinkedBlockingDeque<Integer>();
		Runnable a = new Peek(bdq);
		new Thread(a).start();
	}
}