Skip to content

Register Commands

In this section, we'll walk you through creating a simple command. By the end of this section, you'll have a basic understanding of how to define and register commands with allay.

Create a Command

Let's start with a simple command /hello that greets the command sender.

1
2
3
4
5
6
7
8
import org.allaymc.api.command.SimpleCommand;
import org.allaymc.api.server.Server;

public class HelloCommand extends SimpleCommand {
    public HelloCommand() {
        super("hello", "Greets the command sender.");
    }
}

And it's just as simple as that! You've just created a new command with description. Then you need to register the command into the server:

1
2
3
4
5
6
7
8
9
import org.allaymc.api.plugin.Plugin;
import org.allaymc.api.registry.Registries;

public class MyPlugin extends Plugin {
    @Override
    public void onEnable() {
        Registries.COMMANDS.register(new HelloCommand());
    }
}

Add permissions

By the default, only the one who has operator permission is able to use the newly created commands. Since we are creating a simple command here, we might want to change its permission for everyone to use.

Let's make the following changes to our code:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
import org.allaymc.api.command.SimpleCommand;
import org.allaymc.api.command.tree.CommandTree;
import org.allaymc.api.permission.DefaultPermissions;
import org.allaymc.api.server.Server;

public class HelloCommand extends SimpleCommand {
    public HelloCommand() {
        super("hello", "Greets the command sender.");
        getPermissions().forEach(DefaultPermissions.MEMBER::addPerm); /*(1)!*/
    }
}
  1. ⭐ See tips

Tip

The getPermissions() method returns a list of permissions that the command requires, and DefaultPermissions.MEMBER is the default permission tree for new players.

DefaultPermissions class contains the following values:

  • DefaultPermissions.OPERATOR: default permission tree for operators.
  • DefaultPermissions.MEMBER: default permission tree for new players.
  • DefaultPermissions.VISITOR: default permission tree for visitors.

Handle the commands

Now, the next step is to handle the commands we just created. Let's say we want to send a "Hello, World!" greeting message to whoever execute this command. It's just a few more lines away from that.

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
import org.allaymc.api.command.SimpleCommand;
import org.allaymc.api.command.tree.CommandTree;
import org.allaymc.api.server.Server;

public class HelloCommand extends SimpleCommand {
    public HelloCommand() {
        super("hello", "Greets the command sender.");
    }

    @Override
    public void prepareCommandTree(CommandTree tree) {
        tree.getRoot()
                .exec(context -> {
                    context.getSender().sendText("Hello World!");
                    return context.success();
                });
    }
}

Now, install your plugin and restart your server. Join the game and type /help hello. You should see the usage information, which indicates that our command has been successfully added to the game!

Now, type /hello, and you should receive the message "Hello World!".

Add parameters to commands

Now, let's say we want to send a custom message to greet the sender instead of "Hello World!". We can add a parameter to the command that accepts a message.

Let's change our code to add an optional parameter message with msg type:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
import org.allaymc.api.command.SimpleCommand;
import org.allaymc.api.command.tree.CommandTree;
import org.allaymc.api.server.Server;

public class HelloCommand extends SimpleCommand {
    public HelloCommand() {
        super("hello", "Greets the command sender.");
    }

    @Override
    public void prepareCommandTree(CommandTree tree) {
        tree.getRoot()
                .msg("message")
                .optional()
                .exec(context -> {
                    String message = context.getResult(0);
                    if (message.isBlank()) { /*(1)!*/
                        context.getSender().sendText("Hello World!");
                    } else {
                        context.getSender().sendText(message);
                    }
                    return context.success();
                });
    }
}
  1. ✅ Here, we checked if the optional parameter is provided.

🥳 And it's done! Now when the users use /hello This is my message!, "This is my message!" will be shown to them instead of "Hello World!".

Tip

To make the parameter mandatory, remove the .optional() method call.

Built-in parameter types

In the section above, we added a parameter with type msg which is a built-in type supported by Allay. You can check the full list of all built-in types currently supported here.

Comments