-2
Ниже приведены мои коды, интерфейс MyQueue и тестер JUnit. Мой код, кажется, в порядке, но тест не сработал, хотя ошибки нет. Может ли кто-нибудь помочь мне разобраться? Спасибо :)JUnit тестирование ошибки Java
MyQueue интерфейс:
import java.util.*;
public interface MyQueue {
void enqueue(int in);
int dequeue() throws NoSuchElementException; // throw exception if isEmpty() is true
int noItems(); // returns the number of items in the array
boolean isEmpty(); // true if queue is empty
}
JUnit код тестер:
import java.util.*;
import junit.framework.TestCase;
public class CircularArrayQueueTest extends TestCase
{
private void checkSize(int length, MyQueue queue)
{
assertEquals("Queue has wrong number of elements", length,
queue.noItems());
if(length == 0)
assertTrue("Queue should be empty", queue.isEmpty());
else
assertTrue("Queue should not be empty", !queue.isEmpty());
}
public void testSimple()
{
MyQueue queue = new CircularArrayQueue();
checkSize(0, queue);
queue.enqueue(3);
checkSize(1, queue);
try
{
assertEquals("Dequeue returns wrong element", 3, queue.dequeue());
} catch(NoSuchElementException e)
{
throw e;
}
checkSize(0, queue);
}
public void testMultiInput()
{
MyQueue queue = new CircularArrayQueue();
for(int i = 0; i < 1000; ++i)
{
int r = (int)Math.round(Math.random());
checkSize(0, queue);
queue.enqueue(r);
checkSize(1, queue);
assertEquals("Dequeue returns wrong element", r, queue.dequeue());
}
}
public void testManyEnqueueDequeue()
{
CircularArrayQueue queue = new CircularArrayQueue();
int cnt = 0;
for(int i = 0; i < 100000; ++i)
{
if(Math.random() > 0.5)
{
queue.enqueue(i);
cnt++;
} else
{
if(!queue.isEmpty())
{
queue.dequeue();
cnt--;
}
}
assertEquals("Correct number of items", cnt, queue.noItems());
}
}
public void testLargeQueue()
{
MyQueue queue = new CircularArrayQueue();
int[] r = new int[ 1000 ];
for(int i = 0; i < r.length; ++i)
{
r[ i ] = (int)Math.round(Math.random());
checkSize(i, queue);
queue.enqueue(r[ i ]);
}
for(int i = 0; i < r.length; ++i)
{
assertEquals("Dequeue returns wrong element", r[ i ],
queue.dequeue());
checkSize(r.length - i - 1, queue);
}
for(int i = 0; i < r.length; ++i)
{
r[ i ] = (int)Math.round(Math.random());
checkSize(i, queue);
queue.enqueue(r[ i ]);
}
for(int i = 0; i < r.length; ++i)
{
assertEquals("Dequeue returns wrong element", r[ i ],
queue.dequeue());
checkSize(r.length - i - 1, queue);
}
}
public void testThrows()
{
MyQueue queue = new CircularArrayQueue();
int[] r = new int[ 1000 ];
for(int i = 0; i < r.length; ++i)
{
r[ i ] = (int)Math.round(Math.random());
checkSize(i, queue);
queue.enqueue(r[ i ]);
}
for(int i = 0; i < r.length; ++i)
{
assertEquals("Dequeue returns wrong element", r[ i ],
queue.dequeue());
checkSize(r.length - i - 1, queue);
}
boolean throwsCorrectly = false;
try
{
queue.dequeue();
} catch(NoSuchElementException e)
{
throwsCorrectly = true;
}
assertTrue("Throws when dequeuing empty queue", throwsCorrectly);
}
public void testResize()
{
CircularArrayQueue queue = new CircularArrayQueue();
assertTrue("Initial capacity too large", queue.getCapacityLeft() <= 1024);
for(int i = 0; i < 1000; ++i)
{
queue.enqueue(i);
}
int currentCapacity = queue.getCapacityLeft();
while(currentCapacity > 0)
{
queue.enqueue(9);
currentCapacity--;
assertEquals("Array size should not change", currentCapacity,
queue.getCapacityLeft());
}
assertTrue("Should have reached capacity", queue.getCapacityLeft() == 0);
queue.enqueue(42);
assertTrue("Should have resized array",
currentCapacity < queue.getCapacityLeft());
currentCapacity = queue.getCapacityLeft();
for(int i = 0; i < 100; ++i)
{
queue.enqueue(i);
currentCapacity--;
assertEquals("Resizing too often (inefficient)", currentCapacity,
queue.getCapacityLeft());
}
}
}
Ниже мой собственный написанный код:
import java.util.NoSuchElementException;
public class CircularArrayQueue implements MyQueue{
private static final int capacity = 10;//Initial Capacity
private Integer[] Queue;
private final int count; // capacity
private int head = 0;
private int tail = 0;
// Creates an empty queue using the capacity.
public CircularArrayQueue(){
count = capacity;
Queue = new Integer[count];
}
// Adds the specified element to the tail of the queue, expanding
// the capacity of the queue array if necessary.
public void enqueue(int in) {
if(isFull()){
expandCapacity();
}
Queue[tail] = in;
tail = (tail + 1) % Queue.length;
}
// Creates a new array to store the contents of the queue with
// twice the capacity of the old one.
public void expandCapacity() {
Integer[] larger = ((Integer[]) (new Integer[Queue.length * 2]));
for (int scan=0; scan < Queue.length; scan++) {
larger[scan] = Queue[head];
head = (head+1) % Queue.length;
}
head = 0;
tail = Queue.length - 1;
Queue = larger;
}
// Removes the element at the head of the queue and returns a
// reference to it. Throws an EmptyCollectionException if the
// queue is empty.
public int dequeue() throws NoSuchElementException {
int item;
if(isEmpty()){
throw new NoSuchElementException();
}else{
item = Queue[head];
Queue[head] = null;
head = (head + 1);
}
return item;
}
// Returns the number of elements currently in this queue.
public int noItems() {
if(tail > head)
return tail - head;
return count - head + tail;
}
// Returns true if this queue is empty and false otherwise.
public boolean isEmpty() {
return (tail == head) ? true : false;
}
public boolean isFull() {
int diff = tail - head;
if(diff == -1 || diff == (count -1))
return true;
return false;
}
public int getCapacityLeft() {
if(isFull()){
return 0;
}else{
return count-noItems();
}
}
}
Несоблюдение какого сообщения об ошибке? –
Для воспроизведения 'интерфейс MyQueue' отсутствует. –
@ChristianHujer код обновлен с помощью интерфейса MyQueue. – Hilton