问使用队列的Java Pig拉丁语句子翻译器

EN

public static void main (String[] args)
 {


    Scanner scan = new Scanner (System.in);

    QueueList word = new QueueList();

    String message;
    int index = 0;
    char firstch;
    System.out.print ("Enter an English sentence: ");
    message = scan.nextLine();
    System.out.println ("The equivalent Pig Latin sentence is: ");

    firstch = Character.toLowerCase(message.charAt(0));


            if (firstch != 'a' && firstch != 'e' && firstch != 'i' && firstch != 'o' && firstch != 'u' 
                    && firstch != ' ')
                {
                    for (index = 1; index < message.length(); index++)

                        {
                            word.enqueue(new Character(message.charAt(index)));
                        }

                    word.enqueue(new Character (firstch));
                    word.enqueue(new Character ('a'));
                    word.enqueue(new Character ('y'));
                    word.enqueue(new Character(' '));

                }

            else if (firstch == 'a' || firstch == 'e' || firstch == 'i' || firstch == 'o' || firstch == 'u')
            {
                while (message.charAt(index) != ' ')
                {
                for (index = 1; index < message.length(); index++)
                        {   
                            word.enqueue(new Character(message.charAt(index)));
                        }
                }
                word.enqueue((firstch));
                word.enqueue( ('y'));
                word.enqueue((' '));
            }
            else if (message.charAt(index) == ' ')
            {
                index++;
                firstch = message.charAt(index);
            }



    while (!word.empty())
        System.out.print(word.dequeue());

}

// QueueList.java
//
// Class QueueList definition with composed List object.    

package MyQueue;

public class QueueList {

    private List a_queue;

    public QueueList() {
        a_queue = new List( "queue" );
    }

    public Object peek() throws EmptyListException {
        if (a_queue.isEmpty())
            return null;
        else
            return a_queue.getFirstObject();
    }

    public void print() {
        a_queue.print();
    }

    public void enqueue(Object object) {
        a_queue.insertAtBack(object);
    }

    public Object dequeue() throws EmptyListException {
        return a_queue.removeFromFront();
    }

    public boolean empty() {
        return a_queue.isEmpty();
    }

}