JFFL - Javassist Framework for Forge Loader
JFFL is a bytecode manipulation library for Minecraft Forge based on Javassist, providing Mixin-like declarative patch injection capabilities. It allows developers to modify classes from Minecraft and other mods at runtime using annotations, without the need to write low-level ASM or Javassist code directly.
Features
- Declarative Annotation-Driven
- Callback Handlers
- Mapping Remapping Support
- Flexible Injection Points
Installation and Dependencies
repositories {
// Put the .jar of JFFL mod into the libs folder
flatDir {
dir 'libs'
}
}
// Write in dependencies (replace {versino} with the actual version number):
dependencies {
implementation fg.deobf("wertygh:jffl:{version}")
}
Relationship with Mixin
JFFL is not a replacement for Mixin but rather provides an alternative option. Both can coexist, though applying both to the same class is not recommended as it may lead to unexpected conflicts. JFFL's advantages include:
- Lightweight, based on Javassist source-level operations, easier to debug
- Supports dynamic callback registration without generating synthetic methods
Development and Debugging
In development environment (jffl.dev=true):
- JFFL outputs detailed logs
- Use @DumpClass to output modified classes to the .jffl-dump directory
- Supports direct use of MCP/Mojang names without loading mappings
License
BSD Zero Clause License
Contribution and Feedback
Issues and Pull Requests are welcome! Project author: wertygh
