java - 实现的 LinkedQueue 中的 pop 方法正在删除所有值，而不是第一个值

Question

通过这个 LinkedQueue 的实现，除了 pop() 方法之外的所有方法都可以正常工作。当使用 pop() 方法时，堆栈中的所有值都会消失，当它应该只删除第一个值时，堆栈会变成空

这是 LinkedQueue 类

import java.util.NoSuchElementException;

    public class LinkedQueue
    {
        Node front, rear;
        int size;

        public LinkedQueue()
        {
            front = null;
            rear = null;
            size = 0;
        }

        public boolean isEmpty()
        {
            if(front == null)
                return true;
            else
                return false;
        }

        public int getSize()
        {
            return size;
        }

        public void push(int data)
        {
            Node n = new Node(data);
            if(isEmpty())
                front = rear = n;
            else
            {
                rear.setLink(n);
                rear = n;
            }

            size++;
        }

        public int pop()
        {
            Node temp = new Node(front.getData());
            if(isEmpty())
            {
                throw new IllegalAccessError();
            }
            else
            {
                front = temp.getLink();
                size--;
            }

            return temp.getData();
        }

        public int peek()
        {
            if (isEmpty())
            {
                throw new NoSuchElementException("Stack is empty.");
            }
            else
            {
                return front.getData();
            }
        }

        public String toString()
        {
            Node tempFront = front;
            String returnStr = "Stack: [";
            while(tempFront != null)
            {
                returnStr += tempFront.getData() + ", ";
                tempFront = tempFront.getLink();
            }

            returnStr += "]";

            return returnStr;
        }
    }

这是用于 LinkedQueue 类的驱动程序:

import java.util.Scanner;

    public class Driver
    {
        public static void main(String[] args)
        {
            //declare variables and initialize scanner
            Scanner key = new Scanner(System.in);
            int size, choice, value, end;

            end = 0;

            //declare and initialize the stack
            LinkedQueue queue1 = new LinkedQueue();

            //loop to continue operations
            while(end == 0)
            {
                //print out menu for commands
                System.out.println("\t1) Push \n\t2) Pop \n\t3) Peek \n\t4) Size \n\t5) isEmpty \n\t6) End");
                System.out.print("Please choose an option: ");
                choice = key.nextInt();

                //switch the choice and execute commands
                switch (choice)
                {
                    case 1: System.out.println("Please enter a value: ");
                        value = key.nextInt();
                        queue1.push(value);
                        System.out.println(queue1.toString());
                        break;
                    case 2: queue1.pop();
                        System.out.println(queue1.toString());
                        break;
                    case 3: queue1.peek();
                        System.out.println(queue1.peek());
                        System.out.println(queue1.toString());
                        break;
                    case 4: System.out.println("Size: " + queue1.getSize());
                        System.out.println(queue1.toString());
                        break;
                    case 5: if(queue1.isEmpty())
                    {
                        System.out.println("Stack is empty.");
                    }
                    else
                        System.out.println("Stack is NOT empty.");
                        System.out.println(queue1.toString());
                        break;
                    case 6: end = 1;
                        System.out.println("Goodbye!");
                        break;
                }
            }
        }
    }

我还制作了自己的 Node 类

public class Node
{
    int data;
    Node link;

    //contructor
    public Node(int d)
    {
        data =  d;
        link = null;
    }

    public int getData()
    {
        return data;
    }

    public Node getLink()
    {
        return link;
    }

    public void setData(int d)
    {
        data = d;
    }

    public void setLink(Node n)
    {
        link = n;
    }
}

如前所述，我遇到的唯一问题是 pop() 方法，但如果您看到任何其他也有帮助的错误，我们将不胜感激。

Answer 1

替换

front = temp.getLink();

与

front = front.getLink();