Unittest for the RandomizedQueue class

RandomizedQueueTest.java

import java.util.Iterator;
import java.util.NoSuchElementException;
import junit.framework.TestCase;

public class RandomizedQueueTest extends TestCase {
	RandomizedQueue<Integer> ran;
	
	public void setUp() throws Exception {
		super.setUp();
		ran = new RandomizedQueue<Integer>();
	}
	
	public void tearDown() throws Exception {
		super.tearDown();
		ran = null;
	}
	
	public void testIsEmpty() {
		assertTrue(ran.isEmpty());
		ran.enqueue(5);
		assertFalse(ran.isEmpty());
		ran.dequeue();
		assertTrue(ran.isEmpty());
	}
	
	public void testEnqueueAndDequeue() {
		ran.enqueue(5);
		ran.enqueue(22);
		ran.enqueue(42);
		ran.enqueue(16);
		ran.enqueue(8);
		
		System.out.print("testEnqueueAndDequeue ");
		System.out.printf("%d ", ran.dequeue());
		System.out.printf("%d ", ran.dequeue());
		System.out.printf("%d ", ran.dequeue());
		System.out.printf("%d ", ran.dequeue());
		System.out.printf("%d\n", ran.dequeue());
		
		assertTrue(ran.isEmpty());
		
		try {
			ran.enqueue(null);
			fail("Should throw NullPointerException");
		}
		catch(NullPointerException e) {
			try {
				ran.dequeue();
				fail("Should throw NoSuchElementException");
			}
			catch(NoSuchElementException ex) { }
		}
	}
	
	public void testSample() {
		ran.enqueue(5);
		ran.enqueue(22);
		ran.enqueue(42);
		ran.enqueue(16);
		ran.enqueue(8);

		System.out.print("testSample ");
		
		System.out.printf("%d ", ran.sample());
		System.out.printf("%d ", ran.sample());
		System.out.printf("%d ", ran.sample());
		System.out.printf("%d ", ran.sample());
		System.out.printf("%d ", ran.sample());
		System.out.printf("%d ", ran.sample());
		System.out.printf("%d ", ran.sample());
		System.out.printf("%d\n", ran.sample());
		
		assertEquals(5, ran.size());
		
		for (int i=0; i<5; i++)
			ran.dequeue();
		
		assertTrue(ran.isEmpty());
		
		try {
			ran.sample();
			fail("Should throw NoSuchElementException");
		}
		catch (NoSuchElementException e) { }	
	}
	
	public void testForIterator() {
		ran.enqueue(5);
		ran.enqueue(22);
		ran.enqueue(42);
		ran.enqueue(16);
		ran.enqueue(8);
		
		System.out.print("testForIterator ");
		
		for(Integer i: ran)
			System.out.printf("%d ", i);
		System.out.println();
	}
	
	public void testWhileIterator() {
		ran.enqueue(5);
		ran.enqueue(22);
		ran.enqueue(42);
		ran.enqueue(16);
		ran.enqueue(8);
		
		System.out.print("testWhileIterator ");
		
		Iterator<Integer> it = ran.iterator();
		while(it.hasNext())
			System.out.printf("%d ", it.next());
		System.out.println();		
	}
}