Different meta for different projectiles [NEED HELP!!!!]

Hey!

I have added a custom crafting recipe in my server, which is an Elemental bow.
What I want:
When the player has a ''Elemental Arrow'' (also craftable) he is able to shoot with the elemental Bow.
I don't mind for the effects at this point, I just don't know how to check when the hitted player got hit with a NORMAL arrow or a ELEMENTAL arrow.

And I also need to remove one arrow everytime a elemental arrow has been fired.

Normal bows should be able to shoot elemental arrows, and the other way around, but I only want the special effect once the ELEMENTAL bow shoots the ELEMENTAL arrow. (so now normal bow with elemental arrow etc.)

I hope you can follow me here!
I created a different class for this:

Code:java

package me.dubehh.CoreDefense;
 
import org.bukkit.ChatColor;
import org.bukkit.entity.Arrow;
import org.bukkit.entity.Entity;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.entity.ProjectileHitEvent;
 
public class CraftListener implements Listener {
 
    CoreDefense main;
 
    public CraftListener(CoreDefense main) {
        this.main = main;
    }
 
    @EventHandler
    public void onElemental(ProjectileHitEvent e) {
        Entity entity = e.getEntity();
        if(entity instanceof Arrow){
            Arrow arrow = (Arrow) entity;
            Entity shooter = arrow.getShooter();
            if(shooter instanceof Player) {
                Player player = (Player) shooter;
                if(player.getItemInHand().getItemMeta().equals(ChatColor.AQUA + "Elemental Bow")){
                    arrow.setFireTicks(1000);
                }
 
            }
        }
    }
 
}
 

 

dat Bump

 

You can't compare ItemMeta with a String. Use

Code:java

player.getItemInHand().getItemMeta().getDisplayName().equals(...)

 

Personally, I would add the projectile to an ArrayList and use EntityDamageByEntityEvent to catch it. In the event, check if the Damager is instanceof Arrow and if it is, check if it in the ArrayList. To add it to the ArrayList, check the Arrow's data (and Item data) with ProjectileLaunchEvent.

 

xEpicTaco

Could u format this into a code? (a example one, not spoonfed ;P)

 

Code:java

 
private ArrayList<Projectile> projectiles = new ArrayList<Projectiles>();
@EventHandler
public void onProjectileLaunch(ProjectileLaunchEvent ev)
{
  if(ev.getShooter() instanceof Player)
  {
    //Check if elemental
    projectiles.add(ev.getProjectile());
  }
}
 
@EventHandler
public void onEntityHit(EntityDamageByEntityEvent ev)
{
  if(ev.getDamager() instanceof Projectile)
  {
    Projectile p = (Projectile) ev.getDamager();
    if(projectiles.contains(p))
    {
      //Do Stuff
    }
  }
}

 

xEpicTaco
Hey man!,
Thanks for the reply,
but do you know how I can keep normal arrows and 'Elemental' arrows apart?
Since I only want the special effect when a elemental arrow is fired

 

Put the hitted player/entity on fire instead of the arrow lol

@EDIT: I thought you said something else, sorry...

Well, checking the name is right like you did, just merge your code into the xEpicTaco code...

 

I do arrows this way

Code:

arrow.setMetadata("arrow_type", new FixedMetadataValue(your_main_file, Boolean.valueOf(true)));

Just set that on EntityShootBowEvent and check for it in EntityDamageByEntityEvent with

Code:

if(arrow.hasMetadata("arrow_type")) {

 

That's for entities. He's asking how to tell if it's launching arrows that are elemental (if the ItemStack has elemental properties on it). This I do not know. Anyone have any ideas?

 

xEpicTaco They were essentially doing what I did except they used they're own ArrayList. Adding MetaData makes it a whole lot easier. Also, arrows are entities.

 

He's trying to keep track of if the ItemStack is elemental, then check if when they launched the arrow, if the one they launched was tagged as elemental. I also find it much easier to use a HashMap.

 

xEpicTaco Ahh, I understand now. Also, yeah, HashMap's would be better for multiple types of arrows. Would take less memory than multiple lists anyway (i think), however, that is not likely a concern needed here Dubehh

 

Loogeh xEpicTaco

I didn't try it yet due school work,
but I'll try it tonight and kee you updated.
This is probably for one 'special arrow'. But it would be good to know how I could add more,
so both, thanks for the replies. And ill share my result
Thanks!

 

Dubehh

Code:java

    public ItemStack assignData(ItemStack i, String key, String value) {
        net.minecraft.server.v1_7_R1.ItemStack nms = CraftItemStack.asNMSCopy(i);
        NBTTagCompound tag = null;
        if (nms.tag != null) {
            tag = nms.tag;
        } else {
            nms.tag = new NBTTagCompound();
            nms.tag = tag;
        }
        tag.setString(key, value);
        ItemStack ni = CraftItemStack.asCraftMirror(nms);
        return ni;
    }
 
    public Object readData(ItemStack i, String key) {
        net.minecraft.server.v1_7_R1.ItemStack nms = CraftItemStack.asNMSCopy(i);
        NBTTagCompound tag = null;
        if (nms.tag != null) {
            tag = nms.tag;
        } else {
            nms.tag = new NBTTagCompound();
            nms.tag = tag;
        }
        return tag.get(key);
    }

This uses NMS classes, but if you find a simpler solution, that would be better.
That code would store data, even if the server restarts.
(It works with 1.7.2R0.3)

 

GameplayJDK Loogeh xEpicTaco

Hey,
I somehow can't bind my custom ItemMeta for the 'Elemental Arrow' to a specific MetaData.
I am stuck.

Code:java

 
public class CraftListener implements Listener {
    private ArrayList<Projectile> projectiles = new ArrayList<Projectile>();
 
    CoreDefense main;
 
    public CraftListener(CoreDefense main) {
        this.main = main;
    }
 
    @EventHandler
    public void onProjectileLaunch(ProjectileLaunchEvent e) {
        Entity entity = e.getEntity();
        if (entity instanceof Arrow) {
            ItemStack element = new ItemStack(Material.ARROW);
            ItemMeta elementm = element.getItemMeta();
            elementm.setDisplayName(ChatColor.AQUA + "Elemental Arrow");
            element.setItemMeta(elementm);
            Arrow arrow = (Arrow) entity;
            arrow.setMetadata("elemental", new FixedMetadataValue(main, Boolean.valueOf(true))); // wut
            Entity shooter = arrow.getShooter();
            if (shooter instanceof Player) {
                Player player = (Player) shooter;
                if (player.getItemInHand().getItemMeta().getDisplayName()
                        .equals(ChatColor.AQUA + "Elemental Bow")
                        && player.getItemInHand().getItemMeta().getDisplayName() != null) {
                        projectiles.add(arrow);
                } else {
                    return;
                }
 
            }
        }
    }
 
    @EventHandler
    public void onEntityHit(EntityDamageByEntityEvent e) {
        if (e.getDamager() instanceof Projectile) {
            Projectile p = (Projectile) e.getDamager();
            if (projectiles.contains(p)) {
                Player player = (Player) e.getEntity();
                player.sendMessage(ChatColor.AQUA
                        + "You got hit by a elemental bow!");
 
            }else{
                return;
            }
 
        }
    }
 
}
 

 

Dubehh
Look fine to me, what exactly does not work? Assigning the name or something else?

 

I use a very simple solution for "custom" objects which i want to be seperated from "normal" objects.
Just apply a custom enchantment on the ItemStack - this way you also add a simple value storage for levels and such things via level of the enchantment.

For the shooting part i would have also suggested a HashMap for tracking with the Arrow Entity as key and your custom data as values.

Custom enchantment:

1) Create an own class that extends the Bukkit EnchantmentWrapper like this:

Code:java

public class CustomEnchantment extends EnchantmentWrapper {
    private int maxLevel, startLevel;
    private String name;
 
    public CustomEnchantment(int id, int maxLevel, int startLevel, String name) {
        super(id);
        this.maxLevel = maxLevel;
        this.startLevel = startLevel;
        this.name = name;
    }
 
    @Override
    public int getMaxLevel() {
        return maxLevel;
    }
 
    @Override
    public int getStartLevel() {
        return startLevel;
    }
 
    @Override
    public String getName() {
        return name;
    }
 
    @Override
    public boolean canEnchantItem(ItemStack item) {
        return true;
    }
 
    @Override
    public boolean conflictsWith(Enchantment other) {
        return false;
    }
}

2) Don't forget to register your custom enchantments and store them in a public static variable for later access:
(I've created an extra class for that ... some sort of manager)

Code:java

public class Enchantments {
    public static final CustomEnchantment GCUSTOM = new CustomEnchantment(100,5, 1, "Custom");
    // ... and more
 
    private static final List<CustomEnchantment> enchantments = new ArrayList<CustomEnchantment>();
 
    public static void init() {       
        try {
            Field f = Enchantment.class.getDeclaredField("acceptingNew");
            f.setAccessible(true);
            f.set(null, true);
        } catch (Exception e) {
            e.printStackTrace();
        }
 
        registerEnchantments();
 
        for (CustomEnchantment ench : enchantments) {
            if (Enchantment.getByName(ench.getName()) == null) {
                Enchantment.registerEnchantment(ench);
            }
        }
    }
 
    public static void registerEnchantments() {
        enchantments.add(CUSTOM);
        // ... and more
    }
}

HashMap tracking:

1) Create the HashMap:
(I would recommend using a new class again for HashMap and Arrow handling)

Code:java

public class ElementalArrows {
    private static Map<Entity, CustomData> arrowMap = new HashMap<Entity, CustomData>();
    // CustomData could be anything ... just create a new class CustomData with all needed variables within
 
    public static Map<Entity, CustomData> getArrowMap() {
        return this.arrowMap;
    }
 
    public static void setArrowMap(Map<Entity, CustomData> arrowMap) {
        this.arrowMap = arrowMap;
    }
}

2) Let your events create the entries in the HashMap:
(best you hand them over to your new manager class for better structure)

Code:java

// Create a listener of course
public class EntityListener implements Listener {
 
    @EventHandler
    public void onEntityShootBow(EntityShootBowEvent e) {
        ElementalArrows.onEntityShootBow(e);
    }
}
 
// This goes to your class with the HashMap
 
public static void onEntityShootBow(EntityShootBowEvent e) {
if (e.getEntity() instanceof Player) {
Player player = (Player) e.getEntity();
CustomData customData = new CustomData(); // Create your custom data here with whatever you need
 
arrowMap.put(e.getProjectile(), customData);
}
}
 
 

3) Let your events check for arrows within the HashMap:

Code:java

// This goes to your listener
@EventHandler
public void onEntityDamageByEntity(EntityDamageByEntityEvent e) {
     ElementalArrows.onEntityDamageByEntity(e);
}
 
 
// This goes to your class with the HashMap
 
public static void onEntityDamageByEntity(EntityDamageByEntityEvent e) {
        if (e.getDamager() instanceof Projectile) {
            Projectile projectile = (Projectile) e.getDamager();
            if (arrowMap.containsKey(projectile)) {
                CustomData customData = arrowMap.get(projectile);
                // do stuff
            }
        }
    }

 

Noxyro
'Cannot use 'this' in a static context'

Noxyro
And to be honest,
I don't understand what I am doing here, I don't want to copy/paste :c.
I have created 4 different classes and my brains hurt..
Do you know a tutorial for this?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

I did not actually tested the code - so yeah this.arrowMap = arrowMap should be ElementalArrows.arrowMap = arrowMap ... I'm dumb sorry ^^

There is no tutorial on this specific topic i guess, but when you never used different classes in your projects before, you should really go through some basic Java tutorials that deal with project structures and classes with their different functions.

Grettings - Noxyro

PS: If demanded I could create a detailed tutorial on how to setup and use custom enchantments?

 

Noxyro

I would like it

@Noxyro
Hey, Thanks for your reply, I won't use it because I need to learn java alot better first.
But your help shall be remembered . Sorry if I wasted your time, but I didn't know it would be that hard (for me).

But for the earlier code I posted:

Code:java

@EventHandler
    public void onProjectileLaunch(ProjectileLaunchEvent e) {
        Entity entity = e.getEntity();
        if (entity instanceof Arrow) {
            ItemStack element = new ItemStack(Material.ARROW);
            ItemMeta elementm = element.getItemMeta();
            elementm.setDisplayName(ChatColor.AQUA + "Elemental Arrow");
            element.setItemMeta(elementm);
            Arrow arrow = (Arrow) entity;
            Entity shooter = arrow.getShooter();
            if (shooter instanceof Player) {
                Player player = (Player) shooter;
                if (player.getItemInHand().getItemMeta().getDisplayName()
                        .equals(ChatColor.AQUA + "Elemental Bow")
                        && player.getItemInHand().getItemMeta().getDisplayName() != null) {
                        projectiles.add(arrow);
                } else {
                    return;
                }
 
            }
        }
    }

I got a NullPointerException on line 40.

Which is:

Code:java

if (player.getItemInHand().getItemMeta().getDisplayName()
                        .equals(ChatColor.AQUA + "Elemental Bow")
                        && player.getItemInHand().getItemMeta().getDisplayName() != null) {

Any idea?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.