Class BeforeReturn

java.lang.Object
org.spongepowered.asm.mixin.injection.InjectionPoint
org.spongepowered.asm.mixin.injection.points.BeforeReturn

public class BeforeReturn extends InjectionPoint

This injection point searches for RETURN opcodes in the target method and returns a list of insns immediately prior to matching instructions. Note that every RETURN opcode will be returned and thus every natural exit from the method except for exception throws will be implicitly specified. To specify a particular RETURN use the ordinal parameter. The injection point accepts the following parameters from At:

ordinal
The ordinal position of the RETURN opcode to match, if not specified then the injection point returns all RETURN opcodes. For example if the RETURN opcode appears 3 times in the method and you want to match the 3rd then you can specify an ordinal of 2 (ordinals are zero-indexed). The default value is -1 which supresses ordinal matching

Example:

   @At(value = "RETURN")

Note that if value is the only parameter specified, it can be omitted:

   @At("RETURN")
  • Constructor Details

  • Method Details

    • checkPriority

      public boolean checkPriority(int targetPriority, int ownerPriority)
      Description copied from class: InjectionPoint
      Runs a priority check in the context of this injection point. A priority check should return true if the injection point is allowed to inject given the relative priorities of the target (a method merged by another mixin with targetPriority) and the incoming mixin with priority mixinPriority.
      Overrides:
      checkPriority in class InjectionPoint
      Parameters:
      targetPriority - Priority of the mixin which originally merged the target method in question
      ownerPriority - Priority of the mixin which owns the owning injector
      Returns:
      true if the priority check succeeds
    • getTargetRestriction

      public InjectionPoint.RestrictTargetLevel getTargetRestriction(IInjectionPointContext context)
      Description copied from class: InjectionPoint
      Returns the target restriction level for this injection point. This level defines whether an injection point is valid in its current state when being used by a restricted injector (currently CallbackInjector).
      Overrides:
      getTargetRestriction in class InjectionPoint
      Parameters:
      context - injection-specific context
      Returns:
      restriction level
    • find

      public boolean find(String desc, org.objectweb.asm.tree.InsnList insns, Collection<org.objectweb.asm.tree.AbstractInsnNode> nodes)
      Description copied from class: InjectionPoint
      Find injection points in the supplied insn list
      Specified by:
      find in class InjectionPoint
      Parameters:
      desc - Method descriptor, supplied to allow return types and arguments etc. to be determined
      insns - Insn list to search in, the strategy MUST ONLY add nodes from this list to the nodes collection
      nodes - Collection of nodes to populate. Injectors should NOT make any assumptions about the state of this collection and should only call the add() method
      Returns:
      true if one or more injection points were found