CODEWITHSUNDEEP
javaarrays
Samuel Quansah
Samuel Quansah

Reputation: 67

How to assign multiple values to a single string in Java with an array?

Currently creating a MUD game as my first serious project in Java, I already have the lore and background set up I just need to start the actual code. I started by first trying to create sets of enemies like this:

//                       Name,     HP,  MP, ATK
enemies[] = {"Weak Skeleton:",    100,   0, 100;
             "Blue Slime:",        50,   0,  25;
             "Novice Rogue Mage:", 25, 100,   0;}

but I obviously can't do that in Java just like that. Is there a way to assign strings a value (kind of like a key-value pair in python, but multiple values assigned to one string) in Java and if so is there a way for me to access and manipulate the integer values assigned to the string?

Upvotes: 1

Views: 11917

Answers (5)

markspace
markspace

Reputation: 11030

Two ways: one is just to use an array. To get "loose" semantics in Java just use Object[]. This works but isn't great.

Object[][] enemies1  = {{"Weak Skeleton:", 100, 0, 100},
                        {"Blue Slime:", 50, 0, 25},
                        {"Novice Rogue Mage:", 25, 100, 0}};

A rather better idea as mentioned is to create a more semantic type like Enemy and create new objects of that type.

Enemy[] enemies1 = { new Enemy( "Weak Skeleton:", 100, 0, 100 ),
                     new Enemy( "Blue Slime:", 50, 0, 25 ),
                     new Enemy( "Novice Rogue Mage:", 25, 100, 0 ) };

Upvotes: 2

buræquete
buræquete

Reputation: 14698

The most proper to do this is to have an object representing the combination of values you have;

public class Enemy {

    private String name;
    private Integer healthPoint;
    private Integer manaPoint;
    private Integer attackPower;

    // getter, setter, constructors
    // example constructor
    public Enemy(String name, Integer hp, Integer mp, Integer ap) {
        this.name = name;
        this.healthPoint = hp;
        this.manaPoint = mp;
        this.attackPower = ap;
    }
}

Then represent this with a map if you'd like, by doing;

List<Enemy> enemies = new ArrayList<>();
enemies.add(new Enemy("Weak Skeleton", 100, 0, 100));
enemies.add(new Enemy("Blue Slime", 50, 0, 25));
enemies.add(new Enemy("Novice Rogue Mage", 25, 100, 0));
Map<String, Enemy> enemyMap = enemies.stream().collect(Collectors.groupingBy(Enemy::getName));

So if you'd need to access and edit any value, it is easy via;

enemyMap.get("Weak Skeleton").setAttackPower(75);

or to add a new enemy;

Enemy dragonBoss = new Enemy("Dragon Boss", 1000, 500, 250);
enemyMap.put(dragonBoss.getName(), dragonBoss);

Though, I'd suggest using some enumeration to identify each enemy, trying to access with name String is not the best practice.

public enum EnemyType { 

    WEAK_SKELETON("Weak Skeleton"), BLUE_SLIME("Blue Slime"), NVC_ROGUE_MAGE("Novice Rogue Mage"); 

    private String name; 

    public String getName() { 
        return this.name; 
    }

    private EnemyType (String name) {
        this.name = name;
    } 
}

And using it as name/key in map.

You'd be better off with Lombok, to chain setters if you'd want, plus it reduces a lot of boilerplate code (getters, setters, constructors). Check @Data with @Accessors(chain = true)

Upvotes: 2

cse
cse

Reputation: 4104

You need to change the approach to think about data as you are changing the language.
What you want to achieve, can be achieve in following way:

 class Data{
    //Choose your access-specified as per your need
    public int hp, mp, atk;
    public Data(int h, int m, int a)
    { hp = h; mp=m; atk=a;}
 }
 ...
 HashMap<String,Data> dataSet = new HashMap<>();
 dataSet.put("val1", new Data(50,40,30));
 ...
 Data d = dataSet.get("val1");
 System.out.println("Value of HP is:" + d.hp);
...

Upvotes: 1

talex
talex

Reputation: 20566

You can create class that represents enemy

public class Enemy {
    private int hp;
    private int mp;
    private int atk;

    public Enemy(int hp, int mp, int atk) {
        this.hp = hp;
        this.mp = mp;
        this.atk = atk;
    }

    public int getHp() {
        return hp;
    }

    public void setHp(int hp) {
        this.hp = hp;
    }

    public int getMp() {
        return mp;
    }

    public void setMp(int mp) {
        this.mp = mp;
    }

    public int getAtk() {
        return atk;
    }

    public void setAtk(int atk) {
        this.atk = atk;
    }
}

and then use it like this:

    HashMap<String, Enemy> map = new HashMap<>();

    map.put("Weak Skeleton", new Enemy(100, 0, 100));
    map.put("Blue Slime", new Enemy(50, 0, 25));

Upvotes: 1

Tran Ho
Tran Ho

Reputation: 1500

You can use Map in java.

Map<String,List<Integer>> enemies1 = new HashMap<>();
enemies1.put("str1",list1);
enemies1.put("str2",list2);
enemies1.put("str3",list3);

Upvotes: 2

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