java - 变量(可能)超出范围

Question

好的，所以有两个类 Player 和子类 Classes。我使用子类通过 switch 语句在主类中设置玩家统计信息，让用户选择他的类。但由于某种原因，在主类中执行时设置的变量超出了范围。看在我的份上，我不明白为什么会发生这种事

这是Player 类:

public class Player {
private int HP;
private int ATK;
private int DEF;
private int DAMAGE;

    void setHP(int a){
    HP=a;
    }

    void setATK(int a){
    ATK=a;
    }

    void setDEF(int a){
    DEF=a;
    }

    void setDAMAGE(){
    DAMAGE = damageCalculation();
    }

    int damageCalculation(){
    int damage = (2*ATK);    
    return damage;
    }

Player(String Class){
    Classes classes = new Classes();
switch(Class){
    case "Barbarian":
        classes.Barbar();
        System.out.println("Done");
        break;
        case "Rogue":
        break;
    default: System.out.println("Error");
}
}

void getStats(){
System.out.format("Player stats:"
        + "\nHP: %d"
        + "\nATK: %d"
        + "\nDEF: %d"
        + "\nDAMAGE: %d\n",HP,ATK,DEF,DAMAGE);
}
}

这是Classes类(请注意，在子类中获取统计数据返回有效值):

public class Classes extends Player {

public void Barbar(){
Player player = new Player();   
player.setHP(60);
player.setATK(15);
player.setDEF(25);
player.setDAMAGE();
player.getStats();
 }
} 

这是main类:

import java.util.Scanner;
public class SurvivalGame {

   public static void main(String[] args) {
    Scanner scan = new Scanner(System.in,"Windows-1250");
    System.out.println("Enter your class");
    Player player = new Player(scan.nextLine());
    player.getStats(); //here getStats return zeros,
    //possibly out of scope variables if player enters Barbarian
 }
}

Answer 1

public void Barbar(){
Player player = new Player();   

如果仔细观察，您会创建一个新的 Player 并向其添加值，而不是 main 方法中的 Player。