Plugin ASM is a lightweight, Mixin-style bytecode injection framework for Paper/Bukkit servers, enabling declarative method modifications via ASM with no manual bytecode writing.
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。
| 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 |
| 🔥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 |
Java 8 - 21
Minecraft 1.0+
Maven 或 Gradle(仅编译插件时需要)
去Github或Modrinth下载最新的Plugin ASM
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
java -javaagent:pasm-x.x.x.jar -jar paper-1.xx.x-xx.jar
参考Wiki
PASM 已在以下场景通过完整测试:
✅ BEFORE、AFTER、REPLACE、HEAD、TAIL全类型覆盖
✅ 构造函数 <init> 注入
✅ 包含 try-catch-finally 的复杂方法
✅ 参数含 long / double 的宽类型方法(静态→非静态、静态→静态)
✅ 同一方法的多个 REPLACE 冲突检测(仅执行优先级最高者)
✅ 无 pasms 仅有 asms 的配置
✅ Paper 1.21.11 / Java 21
已知限制(将在后续版本改进):
AROUND 注入暂未实现,使用时会降级为 REPLACE 并输出警告。
热加载功能尚不稳定,不建议生产环境使用。
不支持修改 native 方法或抽象方法。
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)
PASM 还是一个年轻的项目,欢迎任何形式的贡献! 你可以:
提交 Issue:报告 Bug 或提议新功能
Pull Request:修复代码、完善文档
分享你的使用案例
期待你的 Star ⭐ 和 Fork 🍴!
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! 🎮🔧
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*.
| 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 |
| 🔥 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. |
Java 8–21
Minecraft 1.0+
Maven or Gradle(only needed when compiling your plugin)
Download the latest Plugin ASM from GitHub or Modrinth
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
java -javaagent:pasm-x.x.x.jar -jar paper-1.xx.x-xx.jar
Refer to the Wiki for detailed usage and examples.
PASM has been fully tested in the following scenarios:
✅ BEFORE, AFTER, REPLACE, HEAD, TAIL–all types covered
✅ Constructor(<init>) injection
✅ Methods containing try‑catch‑finally blocks
✅ Methods with long / double parameters(static → non‑static, static → static)
✅ Conflict detection for multiple REPLACE injectors on the same method(only the highest priority runs)
✅ Configuration with asms only(no pasms)
✅ Paper 1.21.11 / Java 21
Known limitations(to be improved in future versions):
AROUND injection is not yet implemented; using it will fall back to REPLACE and emit a warning.
Hot‑reload is experimental and not recommended for production.
Native methods and abstract methods cannot be modified.
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.
PASM is still a young project, and contributions of any form are welcome! You can:
Submit an issue: report bugs or suggest new features
Pull Request: fix code, improve documentation
Share your use cases
We look forward to your Star ⭐ and Fork 🍴!
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! 🎮🔧
Conversation