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Command Redirects

Redirects are Brigadier's form of aliases and subcommands. The redirect method takes a command node and an optional modifier of context. The command node can be a specific node after a registration of dispathcer, or just the root node.


In vanilla Minecraft, /tell and /w are redirected to /msg, which you can see in MessageCommand.

The example shows how /foo2 redirects to /foo.

  1. public class ExampleMod implements ModInitializer {
  2. @Override
  3. public void onInitialize() {
  4. CommandRegistrationCallback.EVENT.register((dispatcher, registryAccess, environment) -> {
  5. final LiteralCommandNode<ServerCommandSource> fooNode = dispatcher.register(literal("foo")
  6. .executes(context -> {
  7. // For versions below 1.19, replace "Text.literal" with "new LiteralText".
  8. context.getSource().sendMessage(Text.literal("Called /foo with no arguments"));
  10. return 1;
  11. }));
  12. dispatcher.register(literal("foo2").redirect(fooNode));
  13. });
  14. }
  15. }

The redirect tells brigadier to continue parsing the command at another command node.

Chainable Commands

Commands such as /execute as @e[type=player] in the_end run tp ~ ~ ~ are also possible because of redirects.

Let's first consider the vanilla /execute command. There is a node after the literal("execute"). After dispatching subcommands, the dispatcher is redirected to that node (with some modifiers), making you possible to, after completing sub-command arguments, type whatever can be typed directly after /execute. In the sub-command run, the dispatcher is redirected to the root node (dispatcher.getRoot()), allowing you to type another complete command after the word “run”.

Below is an example of a chainable command:

  1. LiteralCommandNode<ServerCommandSource> rootNode = dispatcher.register(literal("fabric_test"));
  2. LiteralCommandNode<ServerCommandSource> root1 = dispatcher.register(literal("fabric_test")
  3. // You can register under the same literal more than once, it will just register new parts
  4. // of the branch as shown below if you register a duplicate branch an error will popup in
  5. // console warning of conflicting commands but one will still work.
  6. .then(literal("extra")
  7. .then(literal("long")
  8. .redirect(rootNode, this::lengthen)) // Return to root for chaining
  9. .then(literal("short")
  10. .redirect(rootNode, this::shorten))) // Return to root for chaining
  11. .then(literal("command")
  12. .executes(ctx -> {
  13. ctx.getSource().sendFeedback(Text.literal("Chainable Command"), false);
  14. return Command.SINGLE_SUCCESS;
  15. })));

The redirect can also modify the CommandSource by use of a “redirect modifier” (SingleRedirectModifier<S>), which is used as a lambda.

  1. .redirect(rootNode, context -> {
  2. // When redirecting, modify the looking direction of the command source.
  3. return ((ServerCommandSource) context.getSource()).withLookingAt(Vec3ArgumentType.getVec3(context, "pos"));
  4. })
tutorial/command_redirects.txt · Last modified: 2023/02/20 05:59 by solidblock