JV8 is no longer maintained.

Take a look at Facebook's React Native for Android, as they necessarily provide a JS <-> JVM interface that is already widely used.

JV8

A simple way to run V8 JavaScript instances from Java.

Warning: This project is **highly experimental**.

Example

V8Runner v8 = new V8Runner();

v8.map("javaSum", new V8MappableMethod {
  @Override
  public V8Value methodToRun(V8Value[] args) {
    double sum = 0;
    for (V8Value val : args) {
      sum += val.toNumber();
    }
    return new v8.val(sum);
  }
});

double sum = v8.runJS("(program)", "javaSum(6, 3, 12, 17, 4);").toNumber();

// sum == 42.0

Supported types

Boolean
Number
String
Function

Function passing and calling

Javascript can pass a Function to the Java context, and Java can call this function back.

v8.map("doSomethingWithFunction", new V8MappableMethod {
  @Override
  public V8Value methodToRun(V8Value[] args) {
  
    // Get the function from JS parameters
    V8Function function = (V8Function)args[0];
    
    // Create a table of arguments to pass
    V8Value newArgs[] = { new V8Number(8) };
    
    // Execute the function with one argument
    V8Value result = v8.callFunction(function, newArgs);
    
    // Get the result
    if (result.isNumber()) {
      double number = result.toNumber(); // 64
    }    
  }
});

v8.runJS("(program)", "doSomethingWithFunction(function(n){ return n * n; })");

Platform support

Currently, only the Android platform is supported, but I intend to support major desktop platforms as well (Linux/Windows/OS X).

This pre-alpha software still in highly experimental stages. Do not use this in production software.

Binaries

A nightly(ish) Android build can be downloaded here.

The tarball should be extracted into the root of a standard android project, and contains the following:

libs/
  jv8.jar
  armeabi/
    gdbserver # FOR DEBUG
    gdb.setup # FOR DEBUG
    libgnustl_shared.so
    libjv8.so

Note: These are debug-only builds for now; i.e. not-optimized and containing debug symbols.

Building

Requirements

You need to be able to build V8 for Android.

svn
git
python
More stuff I'm probably not aware of.

Instructions

First, you must initialize and pull down the v8 git submodule:

# From the root of the project folder:
git submodule init
git submodule update # This will take a while.

Now use the (hackish) build script to create everything you need:

./build.sh -j4 # Use the `-h` flag to see options

Have a snack while you wait. This will result in 3 essential files:

dist/
jv8.tar.gz/
  libs/
    jv8.jar               # Java code
    armeabi/
      libgnustl_shared.so # Android C++ STL support 
      libjv8.so           # JV8 JNI code

There will also be GDB stuff in here; the build script does not generate production binaries, currently, and I Do Not Recommend using this in production.

namuol/jv8

JV8