Package org.spongepowered.asm.mixin.injection.points

Class MethodHead

java.lang.Object

org.spongepowered.asm.mixin.injection.InjectionPoint

org.spongepowered.asm.mixin.injection.points.MethodHead

Direct Known Subclasses:

ConstructorHead

public class MethodHead
extends InjectionPoint

This injection point simply returns the first instruction in the target method body, allowing the injection to be placed at the "head" of the target method. It accepts no parameters and only returns a single insn in all circumstances.

Example:

   @At("HEAD")

Note that for constructors, use of HEAD is discouraged, see instead CTOR_HEAD.

Nested Class Summary

Nested classes/interfaces inherited from class org.spongepowered.asm.mixin.injection.InjectionPoint

InjectionPoint.AtCode, InjectionPoint.Flags, InjectionPoint.RestrictTargetLevel, InjectionPoint.Specifier

Field Summary

Fields inherited from class org.spongepowered.asm.mixin.injection.InjectionPoint

DEFAULT_ALLOWED_SHIFT_BY, MAX_ALLOWED_SHIFT_BY

Constructor Summary

Constructors

Constructor	Description
MethodHead(InjectionPointData data)

Method Summary

Modifier and Type	Method	Description
boolean	checkPriority(int targetPriority, int ownerPriority)	Runs a priority check in the context of this injection point.
boolean	find(String desc, org.objectweb.asm.tree.InsnList insns, Collection<org.objectweb.asm.tree.AbstractInsnNode> nodes)	Find injection points in the supplied insn list

Methods inherited from class org.spongepowered.asm.mixin.injection.InjectionPoint

addMessage, after, and, before, getAtCode, getId, getSlice, getSpecifier, getTargetRestriction, nextNode, or, parse, parse, parse, parse, parse, parse, parse, parse, register, register, setTargetRestriction, shift, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

MethodHead

public MethodHead(InjectionPointData data)

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

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