Java文本冒险游戏随机敌人选择异常：始终选中Assassin

我正在开发一款基于文本的冒险游戏，但随机敌人选择功能无法正常工作：始终只有“Assassin”被选中。我尝试拆分随机选择步骤并打印生成的索引，发现索引是随机的，但显示的敌人始终是同一个。

主类代码 #

package defaultdfs;

import java.util.Random;
import java.util.Scanner;

public class main {

    // System Objects
    static Scanner in = new Scanner(System.in);
    static Random rand = new Random();
    
    //OBJ
    static Entity s = new Entity("Skeleton", 200, 5, 2, 200);
    static Entity z = new Entity("Zombie", 150, 2, 1, 150);
    static Entity w = new Entity("Warrior", 175, 3, 1, 175);
    static Entity a = new Entity("Assasin", 75, 1, 1, 75);
    
    // Game Variables
    static Entity[] enemies = {w, z, s, a};
    static int maxEnemyHealth = 75;
    static int enemyAttackDam = 25;

    // Player Variables
    static int health = 100;
    static int attackDamage = 50;
    static int numHealthPot = 3;
    static int healthPotHealAmount = 30;
    static int healthPotDropChance = 50;
    static int ShieldDropChance = 0;
    static int enemyCounter = 0;
    static int defense = 0;
    static int enemyHealth = 0;
    
    static int damageDealt = 0;
    static int damageTaken = 0;

    //Items
    static boolean sword = false;
    static int swordDropChance = 0;
    
    static boolean running = true;
    
    static Entity enemy;

    public static void main(String[] args) {

        welcome();

        GAME: while (running) {
            System.out.println("-------------------------------------------------");

            
            int ra = rand.nextInt(enemies.length); //RANDOM ENEMY SELECTION in two steps
            enemy = enemies[ra];            

//     enemy = enemies[rand.nextInt(enemies.length)]; //in one step

            System.out.println(ra);
            
            System.out.println("\t# " + enemy.name + " appeared! #\n");

            while (enemy.enemyHealth > 0) {

                monitoring(enemy, Entity.enemyHealth);

                String input = in.nextLine();
                if (input.equals("1")) {
                    damageDealt = rand.nextInt(attackDamage);
                    damageTaken = rand.nextInt(enemyAttackDam);
                    
                    enemy.enemyHealth -= damageDealt;
                    health -= damageTaken;

                    // Iteminfluence
                    health += defense;

                    System.out.println("\t> You strike the " + enemy.name + " for " + damageDealt + " damage.");
                    System.out.println("\t> You recive " + damageTaken + " in retaliation!");

                    if (health < 1) {
                        dead();
                        break;
                    }

                } else if (input.equals("2")) {
                    healingProcess(enemy);
                }

                else if (input.equals("3")) {
                    runOption(enemy);
                    continue GAME;
                }

                else {
                    System.out.println("\tInvalid command!");
                }
            }

            if (health < 1) {
                System.out.println("You limp out of the dungeon, weak from battle!");
                break;
            }

            defmsg(enemy);

            enemyC();

            healpot(enemy);

            defense(enemy);
            
            sword(enemy);

            options();
            
            String input = in.nextLine();
            
            while (!input.equals("1") && !input.equals("2")) {
                System.out.println("Invalid command!");
                input = in.nextLine();
            }

            if (input.equals(input.equals("1"))) {
                System.out.println("You continue on ypur adventure!");
            }

            else if (input.equals("2")) {
                System.out.println("You exit the dungeon, successful from your adventure!");
                break;
            }

        }
        thx();
    }



    private static void sword(Entity enemy) {
        
        if (rand.nextInt(100) < swordDropChance) {

            attackDamage += 5;

            System.out.println(" # The " + enemy.name + " dropped a piece of armor! # ");
            System.out.println(" # You attack now with +5! # ");

        }

        
    }



    private static void defmsg(Entity enemy) {
        System.out.println("-------------------------------------------------");
        System.out.println(" # " + enemy.name + " was defeated! # ");
        System.out.println(" # You have " + health + "HP left. # ");
        
        enemy.enemyHealth = enemy.inHealth;
    }

    private static void options() {
        System.out.println("-------------------------------------------------");
        System.out.println("What would you like to do now? ");
        System.out.println("1. Continue fighting");
        System.out.println("2. Exit dungeon");
    
    }

    private static void thx() {
        System.out.println("#######################");
        System.out.println("# THANKS FOR PLAYING! #");
        System.out.println("#######################");
    }

    private static void welcome() {
        System.out.println("Welcome to the Dungeon!");
        
    }

    private static void attack(int enemyHealth, int damageDealt, int damageTaken) {
        
        enemy.enemyHealth -= damageDealt;
        health -= damageTaken;

        // Iteminfluence
        health += defense;

    }

    private static void dead() {
        System.out.println("\t> You have taken too much damage, you are too weak to go on!");
    }

    private static void monitoring(Entity enemy, int enemyHealth) {
        System.out.println("\tYour HP: " + health);
        System.out.println("\t" + enemy.name + "'s HP: " + enemy.enemyHealth);
        System.out.println("\n\tWhat would you like to do?");
        System.out.println("\t1. Attack");
        System.out.println("\t2. Drink health potion");
        System.out.println("\t3. Run!");

    }

    private static void runOption(Entity enemy) {

        System.out.println("\tYou run away from the " + enemy.name + "!");

    }

    private static void healingProcess(Entity enemy) {

        if (numHealthPot > 0) {

            int prevHealth = health;

            health += healthPotHealAmount;

            if (health == 100) {
                System.out.println("You can not heal yourself!");
            } else if (health > 100) {
                health = 100;
                numHealthPot--;
                System.out.println("\t> You drink a health potion, healing yourself for " + healthPotHealAmount + " . "
                        + "\n\t> You now have " + health + " HP." + "\n\t> You have " + numHealthPot
                        + " health potions left.\n");

            } else {
                numHealthPot--;
                System.out.println("\t> You drink a health potion, healing yourself for " + healthPotHealAmount + " . "
                        + "\n\t> You now have " + health + " HP." + "\n\t> You have " + numHealthPot
                        + " health potions left.\n");

            }

        }

        else {
            System.out.println("\t> You have no health potions left! Defeat enemies for a chance to get one!");
        }

    }

    private static void enemyC() {

        enemyCounter++;

        if (enemyCounter == 1) {
            System.out.println(" # You killed one enemy! # ");
        } else {
            System.out.println(" # You killed " + enemyCounter + " enemies! # ");
        }

    }

    private static void healpot(Entity enemy) {
        if (rand.nextInt(100) < healthPotDropChance) {
            numHealthPot++;
            System.out.println(" # The " + enemy.name + " dropped a health potion! # ");
            System.out.println(" # You now have " + numHealthPot + " heaalth potion(s). # ");
        }

    }

    public static void defense(Entity enemy) {

        if (rand.nextInt(100) < ShieldDropChance) {

            defense += 5;

            System.out.println(" # The " + enemy.name + " dropped a piece of armor! # ");
            System.out.println(" # You now have " + defense + " defensepoints! # ");

        }

    }
}

Entity类代码 #

public class Entity {

    static String name;
    static int enemyHealth = 100;
    static int ShieldDropChance = 0;
    static int swordDropChance = 0;
    static int inHealth = 0;
    
    public static int getSwordDropChance() {
        return swordDropChance;
    }
    public static void setSwordDropChance(int swordDropChance) {
        Entity.swordDropChance = swordDropChance;
    }
    public static int getShieldDropChance() {
        return ShieldDropChance;
    }
    public static void setShieldDropChance(int shieldDropChance) {
        ShieldDropChance = shieldDropChance;
    }
    public static String getName() {
        return name;
    }
    public static void setName(String name) {
        Entity.name = name;
    }
    public static int getEnemyHealth() {
        return enemyHealth;
    }
    public static void setEnemyHealth(int enemyHealth) {
        Entity.enemyHealth = enemyHealth;
    }
    
    public Entity (String name, int enemyHealth, int ShieldDropChance, int swordDropChance, int inHealth) {
        
        this.name = name;
        this.enemyHealth = enemyHealth;
        this.ShieldDropChance = ShieldDropChance;
        this.swordDropChance = swordDropChance;
        this.inHealth = inHealth;
        
        
    }
}

核心问题 #

Entity类的所有字段都被声明为static，这意味着这些变量属于类本身，而非类的实例。当你依次创建Skeleton、Zombie、Warrior、Assassin四个Entity实例时，每个实例都会覆盖静态字段的值。最后创建的Assassin会把name、enemyHealth等静态变量全部替换成自己的属性，所以无论随机选中哪个数组索引，访问的都是类级别的静态变量，自然只会显示Assassin。

修复步骤 #

1. 移除Entity类中所有字段的static修饰符，让每个实例拥有独立属性：

public class Entity {

    String name;
    int enemyHealth = 100;
    int ShieldDropChance = 0;
    int swordDropChance = 0;
    int inHealth = 0;
    
    // ... 其他代码
}

2. 移除所有getter/setter方法的static修饰符，静态方法无法访问实例变量：

public int getSwordDropChance() {
    return swordDropChance;
}
public void setSwordDropChance(int swordDropChance) {
    this.swordDropChance = swordDropChance;
}
public int getShieldDropChance() {
    return ShieldDropChance;
}
public void setShieldDropChance(int shieldDropChance) {
    ShieldDropChance = shieldDropChance;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public int getEnemyHealth() {
    return enemyHealth;
}
public void setEnemyHealth(int enemyHealth) {
    this.enemyHealth = enemyHealth;
}

3. 修正主类中的逻辑错误：主循环的选项判断里，input.equals(input.equals("1"))是错误的，应改为input.equals("1")：

if (input.equals("1")) {
    System.out.println("You continue on your adventure!");
}

完成以上修改后，每个Entity实例会保存自己的独立属性，随机选择敌人时就能正确显示对应敌人的信息了。

内容的提问来源于stack exchange，提问作者VAMPYR CITY