Package org.spongepowered.asm.mixin.gen

Annotation Interface Invoker

@Target(METHOD) @Retention(RUNTIME) public @interface Invoker
Defines an invoker method (also known as a proxy method in a mixin, the method. The annotated method must be abstract and the signature of the method must match the target method precisely.

The target method for an accessor can be specified as part of the decorated method name (eg. callFoo to invoke a target method named foo()) or specified in the annotation value. Invokers for constructors can be created by specifying <init> in the annotation or the fully-qualified class name.

Invokers provide a simple way of gaining access to internal class members in a target class without needing to resort to access transformers, and without the usual need to Shadow a target method. This can both greatly simplify mixins which only contain accessors, and provide for faster development than with access transformers since no re-decompile is needed to put the changes into effect.

Invokers can be used in regular mixins as a way to provide access to a private method without needing to shadow and then manually proxy the method call. They can also be used to create "Accessor Mixins" which are special mixins defined as interfaces which must only contain Accessor and Invoker methods. Unlike normal mixins however, Accessor Mixins are accessible via user code and thus no surrogate "Duck" interface is required to expose the generated methods, the mixin itself acts as its own Duck.

  • Optional Element Summary

    Optional Elements
    Modifier and Type
    Optional Element
    Description
    boolean
    remap
    By default, the annotation processor will attempt to locate an obfuscation mapping for all Invoker methods since it is anticipated that in general the target of a Invoker annotation will be an obfuscated method in the target class.
    String
    value
    Normally the target method name is inflected by examining the annotated method name.

  • Element Details

    • value

      String value
      Normally the target method name is inflected by examining the annotated method name. If the annotated method starts with "call" or "invoke" followed by a capital letter, then the prefix is stripped and the remainder of the method name is used as the target method name.

      However sometimes it maye be desirable to name an accessor method differently to the target method. In this case you may specify the method using its name. Use <init> or the fully qualified name of the target class to invoke a constructor.

      Returns:
      name for the target method, or empty string to inflect using the annotated method name
      Default:
      ""

    • remap

      boolean remap
      By default, the annotation processor will attempt to locate an obfuscation mapping for all Invoker methods since it is anticipated that in general the target of a Invoker annotation will be an obfuscated method in the target class. However since it is possible that the target is not obfuscated, it may be desirable to suppress the compiler warning which would be generated. Setting this value to false will cause the annotation processor to skip remapping for this annotation.
      Returns:
      True to instruct the annotation processor to search for obfuscation mappings for this annotation
      Default:
      true