Bounded priority queue

BoundedPriorityQueue.java

import java.util.PriorityQueue;

public class BoundedPriorityQueue<T> extends PriorityQueue<T> {


    final private int maxSize ;

    public BoundedPriorityQueue(int maxSize) {
        this.maxSize = maxSize;
    }

    @Override
    public boolean add (T  t) {
        boolean added = offer(t);

        if (!added) {
            return false;
        } else if (size() > maxSize) {
            this.remove(this.toArray()[this.size()-1]);
        }
        return true;
    }



}

BoundedPriorityQueueTest.java

import org.junit.Test;

import java.util.PriorityQueue;

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.core.Is.is;
import static org.junit.Assert.assertNull;

public class BoundedPriorityQueueTest {

    private BoundedPriorityQueue<String> queue= new BoundedPriorityQueue(3);

    @Test
    public void testBoundedQueue() {
        queue.add("B");
        queue.add("A");
        queue.add("C");
        queue.add("D");
        assertThat(queue.poll(), is("A"));
        assertThat(queue.poll(), is("B"));
        assertThat(queue.poll(), is("C"));
        assertNull(queue.poll());
    }



}