| # jni (experimental module) |
| |
| This is a utility library to access JNI from Dart / Flutter code, intended as a supplement for `jnigen` code generator, as well as provide the common base components (such as managing the JVM instance) to the code generated by `jni_gen`. |
| |
| This library contains: |
| |
| * functions to access the JNIEnv and JavaVM variables from JNI, and wrapper functions to those provided by JNI. (`Jni.getEnv`, `Jni.getJavaVM`). |
| |
| * Functions to spawn a JVM on desktop platforms (`Jni.spawn`). |
| |
| * Some utility functions to make it easier to work with JNI in Dart; eg: To convert a java string object to Dart string (mostly as extension methods on `Pointer<JniEnv>`). |
| |
| * Some Android-specific helpers (get application context and current activity references). |
| |
| * Some helper classes and functions to simplify one-off uses (`JniObject` and `JniClass` intended for calling functions by specifying the name and arguments. It will reduce some boilerplate when you're debugging. Note: this API is slightly incomplete). |
| |
| This is intended for one-off / debugging uses of JNI, as well as providing a base library for code generated by jni_gen. |
| |
| __To interface a complete java library, look forward for `jni_gen`.__ |
| |
| ## Platform support |
| The focus of this project is Flutter Android, since Flutter Android apps already have a JVM, and JNI enables interop with existing Java code and Android Platform APIs. This project also (partially) supports Linux desktop by spawning a JVM through JNI. |
| |
| ## Version note |
| This library is at an early stage of development and we do not provide backwards compatibility of the API at this point. |
| |
| ## Documentation |
| The test/ directory contains files with comments explaining the basics of this module, and the example/ directory contains a flutter example which also touches some Android-specifics. |
| |
| Using this library assumes some familiarity with JNI - it's threading model and object references, among other things. |
| |
| ## jni_gen |
| |
| This library is a part of `jni_gen` - a 2022 GSoC project. |
| |
| The broader aim of jni_gen is making Java APIs accessible from dart in an idiomatic way. |
| |
