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Plugin ASM
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Plugin ASM

by laolizhennui · on Modrinth

Plugin ASM is a lightweight, Mixin-style bytecode injection framework for Paper/Bukkit servers, enabling declarative method modifications via ASM with no…

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Plugin ASM — screenshot 1

中文

Plugin ASM

PASM 是一个轻量级、Mixin 风格的字节码注入框架,专为 Paper / Folia 服务端设计。 它允许你通过简单的注解,在运行时修改任意类的字节码——无需反射,无需继承,无性能损耗。

🎯 目标:让 Bukkit/Paper 插件开发者能像写普通 Java 一样实现热修补、API 增强、事件拦截等操作,而不触碰复杂的 ASM 细节。


✨ 核心特性

特性 说明
🚀 Mixin 式注入 @Pasm + @Inject 定义目标类与方法,框架自动合并字节码
🩸全注入类型 BEFORE / AFTER / REPLACE / HEAD / TAIL(AROUND 降级为 REPLACE)
🏗️ 构造函数注入 支持 ,自动插入 super() 之后
🔥异常处理兼容 try-catch-finally 完整复制,标签映射正确
📏宽类型自动偏移 long / double 参数自动处理双槽位,无需手动计算 this 偏移
⚔️ REPLACE 独占 同一方法若存在 REPLACE,自动忽略其他注入(符合 Mixin 规范)
🧩 ASM 处理器钩子 在 pasm.json 中声明 asms 数组,实现 PasmAsmProcessor 接口,可在 premain 前后执行自定义字节码操作
📦插件式扫描 将 pasm.json 放入插件 Jar 根目录,PASM 自动扫描所有注入点

📋 环境要求


📥 使用方法

  1. 去Github或Modrinth下载最新的Plugin ASM

  2. 添加到服务器根目录,添加后,结构应该如下:

server
| -> paper-1.xx.x-xx.jar
| -> pasm-x.x.x.jar
| -> plugins
    | -> 一些插件.jar
  1. 修改你的启动命令,修改后,应该如下:
java -javaagent:pasm-x.x.x.jar -jar paper-1.xx.x-xx.jar

使用Plugin ASM来字节码注入

参考Wiki


🧪 测试与兼容性

PASM 已在以下场景通过完整测试:

已知限制(将在后续版本改进):


📦 如何构建 PASM 本体(仅框架维护者)

git clone https://github.com/laolizhennui/Plugin-ASM.git
cd Plugin-ASM
mvn clean package

生成产物:target/pasm-x.x.x.jar(这就是 Java Agent)


🤝 参与贡献

PASM 还是一个年轻的项目,欢迎任何形式的贡献! 你可以:

期待你的 Star ⭐ 和 Fork 🍴!


📄 许可证

LGPL License

Copyright © 2026 laolizhennui


最后——PASM 并不是要取代 Mixin,而是为 Paper 开发者提供一个更简单、更符合直觉的字节码注入选择。 如果你喜欢它,请告诉你的朋友;如果你遇到问题,请告诉我们。 Happy Coding! 🎮🔧


English

Plugin ASM

PASM is a lightweight, Mixin‑style bytecode injection framework designed specifically for Paper / Folia server environments. It allows you to modify the bytecode of arbitrary classes at runtime using simple annotations—no reflection, no inheritance, zero performance penalty.

🎯 Goal: Let Bukkit/Paper plugin developers implement hot‑patches, API enhancements, event interceptors, and more—* just by writing plain Java, without touching complex ASM internals*.


✨ Core Features

Feature Description
🚀 Mixin‑style injection @Pasm + @Inject define target class & method; the framework merges bytecode automatically.
🩸 Full injection types BEFORE / AFTER / REPLACE / HEAD / TAIL (AROUND falls back to REPLACE with a warning).
🏗️ Constructor injection Supports ; automatically inserted after super() call.
🔥 Exception‑handler compatibility Full replication of try‑catch‑finally blocks; correct label mapping.
📏 Automatic wide‑type offset long / double parameters are handled as double‑slots; no manual calculation of this offset.
⚔️ Exclusive REPLACE If a method has multiple REPLACE injections, only the one with highest priority is applied.
🧩 ASM processor hooks Declare asms array in pasm.json; implement PasmAsmProcessor interface to run custom bytecode operations before/after premain.
📦 Plugin‑style scanning Place pasm.json in your plugin JAR root; PASM automatically discovers all injection points.

📋 Environment Requirements


📥 Installation & Setup

  1. Download the latest Plugin ASM from GitHub or Modrinth

  2. Place it in your server root directory. The structure should look like this:

server
| -> paper-1.xx.x-xx.jar
| -> pasm-x.x.x.jar
| -> plugins
    | -> some-plugin.jar
  1. Modify your startup command accordingly:
java -javaagent:pasm-x.x.x.jar -jar paper-1.xx.x-xx.jar

🛠️ Using Plugin ASM for Bytecode Injection

Refer to the Wiki for detailed usage and examples.

🧪 Testing & Compatibility

PASM has been fully tested in the following scenarios:

Known limitations(to be improved in future versions):


📦 How to Build PASM Itself(Framework Maintainers Only)

git clone https://github.com/laolizhennui/Plugin-ASM.git
cd Plugin-ASM
mvn clean package

Output artifact: target/pasm-x.x.x.jar–this is the Java Agent.


🤝 Contributing

PASM is still a young project, and contributions of any form are welcome! You can:

We look forward to your Star ⭐ and Fork 🍴!


📄 License

LGPL License

Copyright © 2026 laolizhennui


Finally–PASM is not meant to replace Mixin, but to offer Paper developers a simpler, more intuitive choice for bytecode injection. If you like it, tell your friends; if you encounter problems, tell us. Happy Coding! 🎮🔧

Quick facts

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