ArrayBlockingQueue contains() method in Java

ArrayBlockingQueue is bounded, blocking queue that stores the elements internally backed by an array.
- ArrayBlockingQueue class is a member of the Java Collections Framework.
- Bounded means it will have a fixed size, you can not store number the elements more than the capacity of the queue.
- The queue also follows FIFO (first-in-first-out) rule for storing and removing elements from the queue.
- If you try to put an element into a full queue or to take an element from an empty queue then the queue will block you.
The contains(Object o) method returns true if queue contains the object o passed as parameter. We can say that method returns true if and only if this queue contains at least one element e which is equal to object o passed as parameter i.e. o.equals(e).
Syntax:
public boolean contains(Object o)
Parameter:
o – object to check whether queue contains the specified object.
Return Value:
true if this queue contains the object
Below program illustrate contains method of ArrayBlockingQueue.
Example 1
// Java Program Demonstrate contains(Object o)// method of ArrayBlockingQueue. import java.util.concurrent.ArrayBlockingQueue; public class GFG { public static void main(String[] args) { // define capacity of ArrayBlockingQueue int capacity = 5; // create object of ArrayBlockingQueue ArrayBlockingQueue<Integer> queue = new ArrayBlockingQueue<Integer>(capacity); // Add elements to ArrayBlockingQueue queue.add(23); queue.add(32); queue.add(45); queue.add(12); // check whether queue contains 23 boolean response1 = queue.contains(23); // print after applying contains method with 23 as parameter System.out.println("queue contains 23 : " + response1); // check whether queue contains 99 boolean response2 = queue.contains(99); // print after applying contains method with 99 as parameter System.out.println("queue contains 99 : " + response2); }} |
Output:
queue contains 23 : true queue contains 99 : false
Example 2
// Java Program Demonstrate contains(Object o)// method of ArrayBlockingQueue.import java.util.concurrent.ArrayBlockingQueue; public class GFG { // create a User Object with name and age as attribute public class User { public String name; public String age; User(String name, String age) { this.name = name; this.age = age; } } // Main Method public static void main(String[] args) { GFG gfg = new GFG(); gfg.containsMethodExample(); } // Method to give example of contains function public void containsMethodExample() { // define capacity of ArrayBlockingQueue int capacity = 5; // create object of ArrayBlockingQueue ArrayBlockingQueue<User> queue = new ArrayBlockingQueue<User>(capacity); User user1 = new User("Aman", "24"); User user2 = new User("Amar", "23"); User user3 = new User("Sanjeet", "25"); User user4 = new User("Suvo", "26"); // Add Objects to ArrayBlockingQueue queue.add(user1); queue.add(user2); queue.add(user3); queue.add(user4); User user5 = new User("Ravi", "22"); // check whether queue contains User1 boolean response1 = queue.contains(user1); // print after applying contains method with user1 as parameter System.out.println("queue contains User having name " + user1.name + " : " + response1); // check whether queue contains User5 boolean response2 = queue.contains(user5); // print after applying contains method with user1 as parameter System.out.println("queue contains User having name " + user5.name + " : " + response2); }} |
Output:
queue contains User having name Aman : true queue contains User having name Ravi : false



