Injector

Injector is a Kotlin / Java library for modifying classes at runtime using ASM

Installation

repositories {
    mavenCentral()
    
    // Required for Koffee, which is a dependency of Injector
    maven("https://maven.hackery.site/")
    
    // Required to retrieve Injector from GitHub
    maven("https://jitpack.io/")
}

dependencies {
    implementation("com.github.cbyrneee:Injector:latest-commit-hash")
}

Usage

EntryPoint.kt

fun main(args: Array<String>) {
    val classLoader = InjectorClassLoader()
    Thread.currentThread().contextClassLoader = classLoader

    // Example of invoking your class through the classloader
    val clazz = classLoader.loadClass("Example")
    clazz.getMethod("run").invoke(clazz.getDeclaredConstructor().newInstance())
}

Example.kt

fun run() {
    val classLoader = Thread.currentThread().contextClassLoader as InjectorClassLoader
    classLoader.addTransformer(InjectorClassTransformer())
       
    injectMethod<Test>("Test", "main", "()V") { (params, fields, returnInfo) -> // this: Test ->
        println("Injecting before the first instruction in Test#main and returning!")
        returnInfo.cancel()
    }
}

For a full example, check out the example project

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please update the example project if making a major change.

License

GPL 3.0