如何实现一个测试程序（Java）来测试Csc2001LinkedList方法？

Question

I want to know how to implement a test program to test these methods thoroughly, and to do this by using two Csc2001LinkedList objects in the test program, one that is maintained as an ordered list, the other as an unordered list. One aspect of this that I'm aware of is to use the print method to check whether or not the methods are working properly.

Class Csc2001LinkedList

public class Csc2001LinkedList {

    protected Node head;

    public Csc2001LinkedList(Node head)
    {
        this.head = null;
    }

    public Node getHead()
    {
        return head;
    }

    public void addFirst(char c)
    {
        head = new Node(c, head);
    }

    public void addAtEnd(char c)
    {
        Node n = new Node(c, head);
        Node temp = head;

        while(temp.next != null)
        {
            temp = temp.next;
        }
        temp.next = n;
    }

    public void addInOrder(char c)
    {
        Node n = new Node(c, head);

        if(isEmpty())
        {
            addFirst(c);
        }
        else
        {
            Node pre = head;
            Node succ = head.next;

            if(n.ch < pre.ch)
            {
                n.next = head;
                head = n;
            }
            else
            {
                while(succ != null && n.ch > succ.ch)
                {
                    pre = succ;
                    succ = pre.next;
                }
                n.next = succ;
                pre.next = n;
            }
        }
    }

    public boolean isEmpty()
    {
        return (head == null);
    }

    public char removeFirst()
    {
        Node temp = head.next;

        if(temp != null)
        {
            head.next = temp.next;
            return temp.ch;
        }
        else
        {
            System.out.println("List is empty");
            return '?';
        }
    }

    public void printList()
    {
        Node temp = head;

        while(temp != null)
        {
            System.out.println(temp.ch + " ");
            temp = temp.next;
        }
    }
}

class Node

public class Node {

    protected char ch;
    protected Node next;

    public Node(char ch, Node next)
    {
        this.ch = ch;
        this.next = null;
    }

}

Answer 1

My suggestion would be to add a third class to your program. This class would be a driver class, and will be used to test the list and node methods thoroughly. You can do this in one of two ways:

• Create a very basic interface in the main method of the driver class. This method will allow you to add chars to the list through keyboard input, and will automatically print the list, and do anything else you want to do once you are done adding. This is a nice option because you don't have to mess with file input. However, it does make it difficult to test methods such as delete without putting a lot of work into the UI.
• Create a method to read in values from files. Create files of chars to test your methods with. In the main method of the driver class, read in the file, add it to a list you create (either ordered or at the end), and print the list. You can then test your other methods on a list whose size and characteristics you can control ahead of time.