创建一个类并使用 awt.point

Question

I am trying to write a class Robot that simulates a robot wandering on an infinite plane. The robot is located at a point with integer coordinates and faces north, east, south, or west. I need to supply methods public void turnLeft(), public void turnRight(), public void move(), public Point getLocation(), public String getDirection() Here is what I have:

import java.awt.Point;

public class Robot 
{
public static void main (String [] args){

    Point location;
    char direction;


    public Robot()
    {
        location = new Point();
     char direction = 'N';
    }

    public void turnLeft()
    {

       char direction = 'S';
    }

    public void turnRight()
    {
       char direction = 'E';
    }

    public void move()
    {
        switch(direction)
        {
            case turnLeft():
            {

                break;
            }

            case turnRight():
            {
                break;
            }
        }
    }

    public Point getLocation()
    {
        return location;
    }

    public String getDirection()
    {
        return direction;
    }
}
}

However I know I'm doing something wrong with the move method .

Answer 1

1. The methods turnLeft() and turnRight() have a return type of void (which means it does not return anything) so you definitely can't use them in your switch-case-expression. You have to put a value behind a case and a void is definitely none.
2. Case only accepts static values like 'a' , "hello world" , 3 , 4.0f or constants that are defined with the static keyword. (When you want to use non-static values use if)
3. As far as I can see you defined the constructor, class members and methods that belong inside class body inside the main method.

And: Think about what you want to do. Do you really want to check for the result of a function or do you want to check for every possible direction ( 'N' , 'S' , 'E' , 'W' )? If so you have to to switch over them. (I also recommend defining them like public static char N='N' etc.; this will prevent you from typing an invalid direction because your IDE will point out the mistake. Even better is using an enum )

I don't want to sound rude but You seem like you don't know a lot about java so I recommend you to actually learn at least some basics of this language.