This plugin demonstrates how a schedulable can transform the Jack IR. In this example, the transformation consists in inserting a ‘System.out.println’ statement at the begininning of every method coming from the source files.
This plugin introduces the following concepts of Jack:
This plugin is hosted in the Jack development branch in AOSP. You can follow the instructions at http://source.android.com/source/downloading.html to setup your machine then execute the following commands
mkdir <jack_project_dir> cd <jack_project_dir> repo init -u https://android.googlesource.com/platform/manifest -b ub-jack repo sync
where <jack_project_dir> is the directory where you want to download the Jack repository.
First you need to initialize the plugin's local dependencies with the following commands
cd toolchain/jack ant dist cd jack-samples ant
Then you can build the plugin using Gradle with the following commands
cd jack-transform-plugin ./gradlew
The plugin .jar file is located at build/libs/jack-transform-plugin.jar.
The plugin's name is com.android.jack.sample.instrumentation.InstrumentationSamplePlugin. Here is an example of command-line to compile source files with this plugin.
java -jar dist/jack.jar --pluginpath jack-samples/jack-transform-plugin/build/libs/jack-transform-plugin.jar --plugin com.android.jack.sample.instrumentation.InstrumentationSamplePlugin --output-dex=<dex_dir> <source_files>
where <dex_dir> is the directory where the classes.dex file is generated and <source_files> are the source files to be compiled.
You can take a look at the Jack's command-line usage with
java -jar dist/jack.jar --help