Spigot Plugin Development - Subtract variable when player dies

Question

I would like to make plugin, that counts player's lives. For example every player has 3 lives. Whenever he dies, he lost 1 life. When he reach 0 lives, he gets banned.

My method looks like this

public class OnPlayerDeath implements Listener {

    private int lives = 3;

    @EventHandler
    public void OnDeath(PlayerDeathEvent event){
        Player player = event.getEntity().getPlayer();
        if (!(player.getKiller() instanceof Player)) 
            player.sendMessage("Died by a something else. You have " + lives + " lives left.");
        else {
            player.sendMessage("Died by a human. You have " + lives + " lives left.");
            lives--;
        }
    }
}

The problem is, whenever player dies, the message shows all the time same variable "3". How to fix that?

Answer 1

You will have to save the amount of lives for each player.

Try using a HashMap

For instance:

public class OnPlayerDeath implements Listener {

// Make new HashMap
private Map<Player, Integer> livesMap = new HashMap<>();

@EventHandler
public void OnDeath(PlayerDeathEvent event){
    Player player = event.getEntity().getPlayer();

    int lives;

    if(!livesMap.containsKey(player)) {
        // Set the default amount of lives to 2. (3 minus 1, since the player already died once)
        lives = 2;
    } else {
        // Subtract one from the player's lives
        lives = livesMap.get(player) - 1;  
    }

    if (!(player.getKiller() instanceof Player)) {
        player.sendMessage("Died by a something else. You have " + lives + " lives left.");
    } else {
        player.sendMessage("Died by a human. You have " + lives + " lives left.");
    }

    // Update new life count
    livesMap.put(player, lives);
}

}

A HashMap allows you to save a value for each key. In this case the life count for each player.