How to make a Minecraft economy plugin

Step by step

1. 1.Decide what the plugin is

   Either it is the economy (it stores balances and registers itself as the Vault economy), or it uses an existing economy through Vault (a shop, bounties, a job plugin). Most servers need one of each, not two economies.

2. 2.Pick the server and version

   Write the server software and version, for example Paper 1.21.4. The plugin is built for that version's API and Java level.

3. 3.List the commands and rules

   /balance, /pay <player> <amount>, /baltop, and admin commands such as /eco give|take|set. Add the starting balance, the currency name, decimals and a minimum payment.

4. 4.Choose where balances are saved

   SQLite for one server, MySQL if several servers must share the same balances. Money must survive restarts and crashes, so it is never kept only in memory.

5. 5.Let Codexe write and build it

   Describe the plugin and name Vault explicitly so it is added as a dependency. Codexe writes the Java code, plugin.yml and config.yml, compiles it and fixes build errors before the project is Ready.

6. 6.Test payments in game

   Press Try it now and join the test server. Pay between two accounts, try amounts that are too large, negative or not numbers, then restart and check the balances are still there.

7. 7.Install it

   Put Vault and your .jar in the server's plugins/ folder and restart. Remove any other economy plugin, or decide which one Vault should use.

How Vault fits in

Vault is a bridge, not an economy. An economy plugin implements Vault's Economy interface and registers it with the server's services manager; other plugins ask for it with getServer().getServicesManager().getRegistration(Economy.class) and call methods such as getBalance, withdrawPlayer and depositPlayer.

So a shop plugin never needs to know which economy you run. In plugin.yml use depend: [Vault] when the plugin cannot work without it, or softdepend when Vault is optional. The Vault API is only needed to compile; Vault itself is installed on the server.

Decisions to write in the request

• Money format: currency name in singular and plural, symbol, how many decimals.
• Limits: starting balance, maximum balance, whether balances can go negative.
• Offline players: whether /pay and /eco work on players who are not online.
• Logging: a transaction log in the database or a file, so staff can check disputes.
• Earning money: killing mobs, playtime rewards, selling items, or only admin commands.

Where to save balances

Example description

"A Paper 1.21.4 economy plugin called Coins that registers itself as the Vault economy. /balance [player], /pay <player> <amount> with a minimum of 1, /baltop with the top 10, and /eco give|take|set for players with coins.admin. New players start with 100 coins. Two decimals. Every payment logged with date, sender, receiver and amount. Balances saved in SQLite. Currency names and every message in config.yml."

Codexe uses SQLite by default when you do not ask for something else. If you ask for MySQL, the plugin is written with a storage-type setting, and the test server gives it a MySQL database of its own while you try it.

Questions