Custom Enchantments. You say what?!

Hello all, CaptainBern here.
Today I will show you how to create your own custom enchantments because I couldn't find any tutorials on how to do it and because the ones I found weren't really "custom", if you know what I'm talking about.

So let's start, oh yeah, this is my first tutorial so don't be mad at me if it isn't clear enough for you

To create custom enchantments you will first have to create a class that extends Enchantment.
Like this:

Code:java

 
package your.custom.enchantment.plugin;
 
import org.bukkit.enchantments.Enchantment;
import org.bukkit.enchantments.EnchantmentTarget;
import org.bukkit.inventory.ItemStack;
 
public class CustomEnchantment extends Enchantment {
 
public CustomEnchantment(int id) {
super(id);
}
 
@Override
public boolean canEnchantItem(ItemStack item) {
return true; //can it enchant items?
}
 
@Override
public boolean conflictsWith(Enchantment other) {
return false; //will it conflict? In this case, nope
}
 
@Override
public EnchantmentTarget getItemTarget() {
return null; //you can define a target here, I just setted it to null...
}
 
@Override
public int getMaxLevel() {
return 2; //the maxmimum level.
}
 
@Override
public String getName() {
return "CoolFlyEnchantThingy"; //the name
}
 
@Override
public int getId(){
return 69;//the id, in this case I choose 69 because no serious person would ever choose that number, lucky me! Oh yeah, the max id = 256
}
 
@Override
public int getStartLevel() {
return 1; //the start level of your enchantment
}
 
}
 

The enchantment will do nothing on it's own. So first we go to our main class, and add this:

Code:java

 
public static CustomEnchantment ench = new CustomEnchantment(69);
 

Now you would think you can simply do:

Code:java

 
item.addUnsafeEnchantment(urMainClass.ench, 1);
 

But nope, this will work but when other plugins try to get the enchantment it will throw an npe. (Or when some minecraft/bukkit thingy tries to get it)
So, yes we will need reflection to register the enchantment.

Like this:

Code:java

 
try{
try {
Field f = Enchantment.class.getDeclaredField("acceptingNew");
f.setAccessible(true);
f.set(null, true);
} catch (Exception e) {
e.printStackTrace();
}
try {
Enchantment.registerEnchantment(ench);
} catch (IllegalArgumentException e){
//if this is thrown it means the id is already taken.
}
}catch(Exception e){
e.printStackTrace();
}
 

(I would place it in my main class under the onEnable() method)
Now you successfully created a custom enchantment.

Because the enchantmentsystem doesn't like reload, ELCHILEN0 made us a nice tool that resets the byId and byName hashmap (the stuff that causes the id error)

Here it is:

Code:java

 
try {
Field byIdField = Enchantment.class.getDeclaredField("byId");
Field byNameField = Enchantment.class.getDeclaredField("byName");
 
byIdField.setAccessible(true);
byNameField.setAccessible(true);
 
@SuppressWarnings("unchecked")
HashMap<Integer, Enchantment> byId = (HashMap<Integer, Enchantment>) byIdField.get(null);
@SuppressWarnings("unchecked")
HashMap<String, Enchantment> byName = (HashMap<String, Enchantment>) byNameField.get(null);
 
if(byId.containsKey(id))
byId.remove(id);
 
if(byName.containsKey(getName()))
byName.remove(getName());
} catch (Exception ignored) { }
 

Leave him a like!

Hope you learned something today!

(Oh yeah, btw this enchantment will not show up in the enchantment table and it will crash the client when a player puts it in an anvil, but with a simpel listener you can avoid this)

 

CaptainBern Does the enchantment show up when you hover over an item which has it?

 

Nicely done, I made a simmiliar thing, But yours seems better.

 

Like on the lore? It never did for me; But you can set it yourself or maybe it will if you define a target item...

Edit: I took al look at the minecraft source, and no, the level will not show up, if you want this then you will have to build against CraftBukkit and use the enchantment class of net.minecraft.server, this includes a method (a) that will display the name; here is it's code:

public String a() {
return "enchantment." + this.name;
}

And then there is the method c that shows up the level;

public String c(int j){
Strings=LocaleI18n.get(this.a());
return s + " " + LocaleI18n.get("enchantment.level." + i);
}

^copy pasted from: https://github.com/Bukkit/mc-dev/blob/master/net/minecraft/server/Enchantment.java#L84 Maybe later I will make a tutorial on how to make a custom enchantments using craftbukkit.

 

This helped me in my thread! Thanks again! +1 (like)

 

Thanks!

 

I think if you add a ItemStack of defined items, you can enchant it in a table.
But then again, just me guessing.

 

Hmmm interesting, but I don't think it will work because it seems like Bukkit and CraftBukkit enchantments are stored/created seperatly, like when you change a bukkit enchantment, it will not automagically change the craftbukkit enchantment, don't get me wrong but in the bukkit enchantment class, the registerEnchantment() method to be precise, in there they never makes use of the vanilla enchantment class where the enchantments for the table get registered. The custom enchantment will get added to the enchantcommand if you use the Enchantment.stopAcceptingRegistrations() after you initilialized your enchantment.(or EnchantmentCommand.buildEnchantments()

 

I've always wondered, does this corrupt worlds if you add a plugin with custom enchants and then remove that plugin while there are items with a custom enchant in the world?

 

jb_aero Nope, but there is a chance the enchantments get's removed / or another plugin will crash because it can't find the enchantment stated in the ench tag.

 

CaptainBern Now put your custom enchanted item in an anvil.

 

Oops I knew I forgot something. Thanks for the reminder ;d

 

I have been using this in a few of my plugins before and have found that when the server is reloaded the enchantment can no longer be typecasted to a CustomEnchantment. After doing some digging I have come to the conclusion that while the enchantments may persist in between reloads they are serialized and unserialized back into the default Enchantment wrapper. This in turn means that what was previously an instance of CustomEnchantment now no longer is an instance of that class. However, you can no longer re-register the enchantment because the id and name are already stored. So to fix issues these issues I added some additional reflection that unregisters the enchantment if it is already registered (See below).

Code:java

try {
	Field byIdField = Enchantment.class.getDeclaredField("byId");
	Field byNameField = Enchantment.class.getDeclaredField("byName");
 
	byIdField.setAccessible(true);
	byNameField.setAccessible(true);
 
	@SuppressWarnings("unchecked")
	HashMap<Integer, Enchantment> byId = (HashMap<Integer, Enchantment>) byIdField.get(null);
	@SuppressWarnings("unchecked")
	HashMap<String, Enchantment> byName = (HashMap<String, Enchantment>) byNameField.get(null);
 
	if(byId.containsKey(id))
		byId.remove(id);
 
	if(byName.containsKey(getName()))
		byName.remove(getName());
} catch (Exception ignored) { }

Hope this helps somebody!

 

ELCHILEN0 I added it to the post, thanks for making this!

 

Anybody know a work-around for the anvil problem? I was thinking just making my own anvil system, but out of curiosity, is there a way to make them work?

 

Nope.

 

Don't know when it happened, but probably around 1.7
Custom enchantments now cause the client to be kicked.

 

CaptainBern the max id for enchantments is actually 255

i use custom enchantments in my plugins in 1.7 and it works fine mine does nothing though except add a glow to the item

 

So how do you make the enchantments do things? So far right now I am using it as a form of anti conterfeit process with my in game coupons and for the glow effect for my custom arrows. But if I could get them to do something.....

 

You write the code to do...things...like if you wanted the enchantment to poison people, you'd listen to the EntityDamageByEntityEvent and poison the entity if the attacker had a poison enchant on their item.

 

yeah i figured that would be it.

So, as far as i can tell, arrow entities cant have enchantments on them.

Is this correct?

 

Paxination I have no idea if this would or wouldn't work. As some people reported this to be broken now, I wouldn't rely too much on it. If you're using the enchantment to 'identify' the arrow, than I would rather take a look at the Metadata API.

 

Its working for me. It was an idea to identify the arrow, but i figured you cant put an enchantment on an entity.

Also, i was using metadata, but felt like it was more code than necessary just to tag something.

 

Paxination Keep in mind the metadata api is one of the safest ways to do what you were trying to do. And eventually, with the metadata api you have about 5 - 6 lines. By using a custom enchantment you have to create a whole new class (about 50 lines). Anyways, have a nice day!

 

@CaptainBernWell I needed the enchantment glow effect anyways. This other method I fount did work. Something about adding an enchantment and then removing it?

You too!

 

Paxination Thanks. I don't know about the other method you're talking about so wouldn't know if it is better then this :/

 

DarkBladee12 I think its possible to show the name under the item by edditing the lore.
what you basicly do when you add the enchantment is:
- get a list of the enchants equiped (by doing this, you include the other enchants like protection.)
- translate those to strings, and translate the arabic numbers to roman numbers (see the bottom)
- add them as lore to the itemstack

the only problem I have is it simpely won't show up.
debug does show it up normaly
Maybe becuse the "normal" enchant lore override it?
does anyone know how I can fix this?

This is what I have so far:

Code:java

public static ItemStack addSunEnchant(ItemStack target, int level) {
target.addUnsafeEnchantment(ench, level);
//first, add the enchant (ench) to the itemstack, this is created with the code of this page.
ItemMeta targetmeta = (ItemMeta) target.getItemMeta();
//get the metadata
Map<Enchantment,Integer> enchantments = target.getEnchantments();
//real, not good formated enchants
Iterator<Entry<Enchantment,Integer>> iter = enchantments.entrySet().iterator();
ArrayList<String> enc = new ArrayList<String>();
//array with the correct enchants
while(iter.hasNext()){
Entry<Enchantment,Integer> entry = iter.next();
String lvl = RomanNumbers.run(entry.getValue());
//translate the number, see the bottom for the code
enc.add(entry.getKey().getName().toString() + " " + lvl);
//add the enchant name to the array
}
targetmeta.setLore(enc);
//add the lore
for(String encname : enc) {
log.info(encname);
//debug stuff
}
return target;
//return the itemstack
}

I swear its something stupits, that is always with me xD

Roman numbers:

Code:java

package cookcraft;
 
import java.util.LinkedHashMap;
import java.util.Map.Entry;
 
public class RomanNumbers {
public static String run(int Int) {
LinkedHashMap<String, Integer> roman_numerals = new LinkedHashMap<String, Integer>();
roman_numerals.put("M", 1000);
roman_numerals.put("CM", 900);
roman_numerals.put("D", 500);
roman_numerals.put("CD", 400);
roman_numerals.put("C", 100);
roman_numerals.put("XC", 90);
roman_numerals.put("L", 50);
roman_numerals.put("XL", 40);
roman_numerals.put("X", 10);
roman_numerals.put("IX", 9);
roman_numerals.put("V", 5);
roman_numerals.put("IV", 4);
roman_numerals.put("I", 1);
String res = "";
for(Entry<String, Integer> entry : roman_numerals.entrySet()){
int matches = Int/entry.getValue();
res += repeat(entry.getKey(), matches);
Int = Int % entry.getValue();
}
return res;
}
public static String repeat(String s, int n) {
if(s == null) {
return null;
}
final StringBuilder sb = new StringBuilder();
for(int i = 0; i < n; i++) {
sb.append(s);
}
return sb.toString();
}
 
}
 

 

Bump
CaptainBern maybe?

 

CookCraftHD

Code:

target.setItemMeta(targetmeta)

Also, CONVENTIONS. That "int Int" scared me a bit.

 

I said it, it was stupid....
That second thing was a method I copied from stack overflow

I will test it in a hour, and if it works post my final code.

Thanks, it works!
the only thing is its purple and Italic?
Will have a look with ChatColor

Code:java

public static ItemStack addSunEnchant(ItemStack target, int level) {
target.addUnsafeEnchantment(ench, level);
//first, add the enchant (ench) to the itemstack, this is created with the code of this page.
ItemMeta targetmeta = (ItemMeta) target.getItemMeta();
//get the metadata
Map<Enchantment,Integer> enchantments = target.getEnchantments();
//real, not good formated enchants
Iterator<Entry<Enchantment,Integer>> iter = enchantments.entrySet().iterator();
ArrayList<String> enc = new ArrayList<String>();
//array with the correct enchants
while(iter.hasNext()){
Entry<Enchantment,Integer> entry = iter.next();
String lvl = RomanNumbers.run(entry.getValue());
//translate the number, see the bottom for the code
enc.add(ChatColor.RESET + "" + ChatColor.GRAY + entry.getKey().getName().toString() + " " + lvl);
//add the enchant name to the array
}
targetmeta.setLore(enc);
//add the lore
target.setItemMeta(targetmeta);
return target;
//return the itemstack
}

Edit: Works now, code updated

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