ArrayBlockingQueue add() method in Java
Last Updated :
14 May, 2019
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ArrayBlockingQueue is bounded, blocking queue that stores the elements internally backed by an array.
Java
Java
- 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.
public boolean add(E e)Parameter: e - the element to be added to queue. Return Value: true if adding is successful. Throws: IllegalStateException - if this queue is full NullPointerException - if the specified element is null Example 1 Below program illustrate adding element to ArrayBlockingQueue.
// Java Program to Demonstrate add(E e) method
// of ArrayBlockingQueue.
import java.util.ArrayList;
import java.util.concurrent.ArrayBlockingQueue;
public class GFG {
public static void main(String[] args)
{
// define capacity of ArrayBlockingQueue
int capacity = 10;
// create object of ArrayBlockingQueue
ArrayBlockingQueue<Integer> queue = new ArrayBlockingQueue<Integer>(capacity);
// Add element to ArrayBlockingQueue
queue.add(23);
// print queue after add operation
System.out.println("After adding 23");
System.out.println(queue);
// add more numbers
queue.add(32);
queue.add(45);
queue.add(12);
// print queue after add operation
System.out.println("After adding 32, 45, 12");
System.out.println(queue);
// add more numbers
queue.add(27);
queue.add(67);
// print queue after add operation
System.out.println("After adding 27, 67");
System.out.println(queue);
}
}
Output : After adding 23 [23] After adding 32, 45, 12 [23, 32, 45, 12] After adding 27, 67 [23, 32, 45, 12, 27, 67]Example 2 Below program illustrate adding Element to ArrayBlockingQueue and exception thrown if queue is full.
// Java Program to Demonstrate add(E e) method
// of ArrayBlockingQueue.
import java.util.ArrayList;
import java.util.concurrent.ArrayBlockingQueue;
public class GFG {
public static void main(String[] args)
{
// define capacity of ArrayBlockingQueue to 5 elements
int capacity = 5;
// create object of ArrayBlockingQueue
ArrayBlockingQueue<Integer> queue = new ArrayBlockingQueue<Integer>(capacity);
// Add 5 element to ArrayBlockingQueue
queue.add(23);
queue.add(32);
queue.add(45);
queue.add(12);
queue.add(27);
// print queue after add operation
System.out.println("After adding all 5 elements to queue");
System.out.println(queue);
// check whether queue is full or not.
if (queue.remainingCapacity() == 0) {
System.out.println("Queue is full");
}
else {
System.out.println("Queue is not full");
}
// try to add more elements
// If exception thrown print the exception.
try {
Boolean response = queue.add(27);
}
catch (Exception e) {
e.printStackTrace();
}
}
}
Output :
After adding all 5 elements to queue
[23, 32, 45, 12, 27]
Queue is full
java.lang.IllegalStateException: Queue full
at java.util.AbstractQueue.add(Unknown Source)
at java.util.concurrent.ArrayBlockingQueue.add(Unknown Source)
at defaultpackage.GFG.main(GFG.java:38)
Reference:
https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/ArrayBlockingQueue.html#add(E)
