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JsInterop Generator · Build Status

The jsinterop generator is a java program that takes closure extern files as input and generates Java classes annotated with JsInterop annotations.

This project is used for building Elemental2. Any other uses are experimental. You can use it to generate java APIs for other javascript libraries but we don't provide any official support. Feel free to open issues on the github issue tracker, though.

Run with Bazel

If your project uses Bazel. You can use jsinterop_generator rule to generate java code.

You need to add this repository as an external dependency in your WORKSPACE file

  name = "com_google_jsinterop_generator",

and then define a jsinterop_generator target in your 'BUILD' file

load("@com_google_jsinterop_generator//:jsinterop_generator.bzl", "jsinterop_generator")

    name = "my_thirdparty_lib",
    srcs = ["my_externs.js"],

You can now directly depend on :my_thirdparty_lib target in your java_library rules or build the jar files with bazel build //path/to/your/BUILD/file/directory:my_thirdparty_lib. The jar files with the generated source will created in bazel-bin/path/to/your/BUILD/file/directory.

Run as a standalone java program

Build the generator from source

    $ npm install -g @bazel/bazelisk
    $ alias bazel=bazelisk
  • Clone this git repository:
    $ git clone
  • Build the binary:
        $ cd jsinterop-generator
        $ bazel build //java/jsinterop/generator/closure:ClosureJsinteropGenerator_deploy.jar

The generated jar file can be found at bazel-bin/java/jsinterop/generator/closure/ClosureJsinteropGenerator_deploy.jar

Or download the generator

TODO(dramaix): provides link to download the generator.

Run the generator

Now you have the jar file, just invoke

java -jar /path/to/ClosureJsinteropGenerator_deploy.jar [options] externs_file...

List of required options :

Option Meaning
--output file Path to the jar file that will contain the generated java classes
--output_dependency_file file Path to the dependency file generated by the generator.
--package_prefix string Prefix used when we build the java package
--extension_type_prefix string Value used for prefixing extension types. It's a good practice to pass the name of the library in upper camel case.


Please refer to the contributing document.


Please refer to the license file.


This is not an official Google product.