更改已经建立的双

Question

I have a Java class in school and am rather new to programming. I need to write a short code. So far, I just have a little bit. I have a player class. I'd like to be able to do something where the player's stamina decreases as they walk. But I don't know how to change the health without playing a new player.

Here is my code. There's probably a lot wrong with it. This is my third day of coding.

import java.io.*;
import java.util.Scanner;

public class Controller {
    public static void main(String[] args){           
        System.out.println("Type your name here:");
        Scanner scan = new Scanner(System.in);
        String input = scan.nextLine();         
        Player playerOne = new Player(input);
        playerOne.setStrength(78);
        playerOne.setHealth(99);
        playerOne.setStamina(67);
        playerOne.printplayer();   
    }                   
}

import java.util.Scanner;

public class Player {
    public String name; 
    private String input;
    private double health;
    public double strength;
    public double stamina;

    public Player (String input){
        name = input;
    }

    public void setHealth(double playHp){
        health = playHp;
    }

    public void setStrength(double playStrn){
        strength = playStrn;
    }

    public void setStamina(double playStam){
        stamina = playStam;
    }

    public void printplayer(){
        System.out.println("name  : " + name );
        System.out.println("Health :" + health);
        System.out.println("Strength :" + strength);
        System.out.println("Stamina :" + stamina);
    }
}

Answer 1

You just need to set the new value using setter method of stamina in Player class.

Create getter method in your player class, like below:-

public double getStamina() {
    return stamina;
}

Now see the Controller class, how I am reducing the stamina of playerOne by 1 for every 10 steps:-

public static void main(String[] args){

    System.out.println("Type your name here:");
    Scanner scan = new Scanner(System.in);
    String input = scan.nextLine();         
    //Created the Player object
    Player playerOne = new Player(input);
          playerOne.setStrength(78);
          playerOne.setHealth(99);
          playerOne.setStamina(67);
          playerOne.printplayer();
     //Now moving the player 100 steps/ rule is for every 10 step he loses 1 point in stamina    
          for(int step=0; step<100;step++){
              if(step%10==0){
                  playerOne.setStamina(playerOne.getStamina()-1);
              }
          }
          playerOne.printplayer();

          scan.close();     

    }

Take this as an hint.

Answer 2

If I understand what you are trying to do. You need to create a Timer that will constantly check the status of your player and can give a constant decrease to your player's stamina.

You will need a way to know if your player is walking or not

And a way to change that status. Maybe a KeyListener or a MouseListener

For this kind of Java coding I recommend zetcode

Answer 3

I would suggest you to write a method in Player class as

private void reduceStamina() {
  setStamina(stamina-1); 
}

Then you can call this method from printPlayer before the codes that display output.

reduceStamina()

This will reduce the value of stamina for player each time you print a player. Hope that helps

General Tips: Always keep your attributes/fields in a class private, and only access them using by writing getters and setters for each field/attribute. Your health field is private, good; your stamina field is public, bad. Also you don't need the "input" as a field, since it is only used inside the constructor and is already defined in the parameter.