/** * This method allows the queue to be printed out as a string. * * @return The string that represents all the values held in the array. */ public String toString() { String result = ""; LinearNode<T> current = head; while (current != null) { result = result + (current.getElement()).toString() + "\n"; current = current.getNext(); } return result; }
/** * This method allows the element at the top of the queue to de removed. * * @return The element that is removed * @throws EmptyCollectionException The exception when the queue is empty. */ public T dequeue() throws EmptyCollectionException { if (isEmpty()) { throw new EmptyCollectionException("queue"); } T result = head.getElement(); head = head.getNext(); count--; if (isEmpty()) { tail = null; } return result; }
/** * This method returns the element at the top of the queue if there is an element there. * * @return The first element in the queue. */ public T first() { if (isEmpty()) { throw new EmptyCollectionException("queue"); } return head.getElement(); }