AndroidJSCore is an Android Java JNI wrapper around Webkit's JavaScriptCore C library. It is inspired by the Objective-C JavaScriptCore Framework included natively in iOS 7. Being able to natively use JavaScript in an app without requiring the use of JavaScript injection on a bloated, slow, security-constrained WebView is very useful for many types of apps, such as games or platforms that support plugins. However, its use is artificially limited because the framework is only supported on iOS. Most developers want to use technologies that will scale across both major mobile operating systems. AndroidJSCore was designed to support that requirement.

• Enable full JavaScript support on Android with a Java-only interface (no need to write C/C++ code)
• Maintain feature-level compatibility with the Objective-C JavaScriptCore framework

0.1

See Owen Matthew's excellent blog post on the iOS 7 JavaScriptCore framework for an introduction. This example is taken directly from the post. In the included example application, Owen's entire Objective-C tutorial is implemented in Java.

Browse the example app source for more detailed examples that cover the basics, sharing data and functions between Java and JavaScript, wrapping JS classes in Java which are accessible from both environments, and asynchronous, multi-threaded callbacks between environments.

JSContext context = new JSContext();
context.property("a", 5);
JSValue aValue = context.property("a");
double a = aValue.toNumber();
DecimalFormat df = new DecimalFormat(".#");
System.out.println(df.format(a)); // 5.0
context.evaluateScript("a = 10");
JSValue newAValue = context.property("a");
System.out.printlin(df.format(newAValue.toNumber())); // 10.0

Follow the instructions in this GitHub project from Appcelerator to build the arm and armeabi-v7a libraries. At the moment, the x86 and MIPS builds are not used in AndroidJSCore, but this was only because I couldn't immediately get their JavaScriptCore libraries to build correctly and lost interest. If you want to use them and are able to build, then simply change this line

APP_ABI := armeabi armeabi-v7a

in AndroidJSCoreJNI/jni/Application.mk to add the appropriate platforms.

To build the AndroidJSCoreJNI library, you must have the Android ADT plugin (which includes the SDK) and NDK installed. You will have needed both the SDK and NDK in Step 1 as well. You will also want to make sure you have the CDT plugin if you want to work with the C++ (JNI) code.

Set the path for the NDK you installed in Preferences->Android->NDK->NDK Location

You need to set 2 environment variables. Right-click on AndroidJSCoreJNI project and select Properties->C/C++ Build->Environment. Set the following variables:

• ANDROID_NDK_ROOT to point at your NDK location (e.g. /Users/Eric/workspace/android-ndk-r9d)
• NDK_MODULE_PATH to point to where you installed the JavaScriptCore libraries/includes in step 1 (e.g. /Users/Eric/workspace/AndroidModuleReleases)

You should now be able to build the example app. To use the library in your project, simply right-click on your project and select Properties->Android. In the 'Library' section, add the AndroidJSCoreJNI library and you should be set.

One final note: You should add some memory to Eclipse if you haven't already done that. Here is a Mac tutorial. Bump it up to 1024m (-Xmx1024m). The C/C++ indexer can occasionally lock up Eclipse if you don't.

• Test framework
• Some issues remain around garbage collection, debugging

I am just sticking with Webkit's license, since this thing depends on it.

Copyright (c) 2014 Eric Lange. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.