QuickJS Android wrapper.
git clone --recurse-submodules https://github.com/seven332/quickjs-android.git
Open the folder quickjs-android in Android Studio.
- Add the JitPack repository to your root build.gradle.
allprojects {
repositories {
...
maven { url 'https://jitpack.io' }
}
}- Add quickjs-android dependency to your application build.gradle.
dependencies {
implementation "com.github.seven332:quickjs-android:0.1.0"
}QuickJS quickJS = new QuickJS.Builder().build();
try (JSRuntime runtime = quickJS.createJSRuntime()) {
try (JSContext context = runtime.createJSContext()) {
String script1 = "" +
"function fibonacci(n) {" +
" if (n == 0 || n == 1) return n;" +
" return fibonacci(n - 1) + fibonacci(n - 2);" +
"}";
// Evaluate a script without return value
context.evaluate(script1, "fibonacci.js");
String script2 = "fibonacci(10);";
// Evaluate a script with return value
int result = context.evaluate(script2, "fibonacci.js", int.class);
assertEquals(55, result);
}
}Non-static methods and static methods are supported. Wrap a Java method as a JSFunction, then add the JSFunction to the JSContext. Call it like a normal Javascript function.
QuickJS quickJS = new QuickJS.Builder().build();
try (JSRuntime runtime = quickJS.createJSRuntime()) {
try (JSContext context = runtime.createJSContext()) {
// Non-static method
Integer integer = 0;
JSFunction zeroCompareTo = context.createJSFunction(integer, Method.create(Integer.class, Integer.class.getMethod("compareTo", Integer.class)));
// Add the function to the global object
context.getGlobalObject().setProperty("zeroCompareTo", zeroCompareTo);
assertEquals(-1, (int) context.evaluate("zeroCompareTo(1)", "test.js", int.class));
assertEquals(1, (int) context.evaluate("zeroCompareTo(-1)", "test.js", int.class));
// Static method
JSFunction javaAbs = context.createJSFunctionS(Math.class, Method.create(Math.class, Math.class.getMethod("abs", int.class)));
// Add the function to the global object
context.getGlobalObject().setProperty("javaAbs", javaAbs);
assertEquals(1, (int) context.evaluate("javaAbs(1)", "test.js", int.class));
assertEquals(1, (int) context.evaluate("javaAbs(-1)", "test.js", int.class));
}
}Or create a JSFunction with a callback.
QuickJS quickJS = new QuickJS.Builder().build();
try (JSRuntime runtime = quickJS.createJSRuntime()) {
try (JSContext context = runtime.createJSContext()) {
// Create a JSFunction with a callback
JSValue plusFunction = context.createJSFunction((context, args) -> {
int a = args[0].cast(JSNumber.class).getInt();
int b = args[1].cast(JSNumber.class).getInt();
int sum = a + b;
return context.createJSNumber(sum);
});
context.getGlobalObject().setProperty("plus", plusFunction);
int result = context.evaluate("plus(1, 2)", "test.js", Integer.class);
assertThat(result).isEqualTo(3);
}
}Just evaluate it. Or call JSFunction.invoke().
Use JSContext.executePendingJob() to execute pending job of promises. You may call JSContext.executePendingJob() several times until it returns false.
QuickJS quickJS = new QuickJS.Builder().build();
try (JSRuntime runtime = quickJS.createJSRuntime()) {
try (JSContext context = runtime.createJSContext()) {
context.evaluate("a = 1;Promise.resolve().then(() => { a = 2 })", "test.js");
assertEquals(1, context.getGlobalObject().getProperty("a").cast(JSNumber.class).getInt());
// Execute the pending job
assertTrue(context.executePendingJob());
assertEquals(2, context.getGlobalObject().getProperty("a").cast(JSNumber.class).getInt());
// No pending job
assertFalse(context.executePendingJob());
}
}Java values are converted to Javascript values when calling Java methods in Javascript scripts. Javascript values are converted to a Java values when receiving return values from evaluated Javascript scripts. QuickJS Android supports primitive types, string, array.
QuickJS quickJS = new QuickJS.Builder().build();
try (JSRuntime runtime = quickJS.createJSRuntime()) {
try (JSContext context = runtime.createJSContext()) {
String[] result = context.evaluate("['hello', 'world']", "test.js", String[].class);
assertArrayEquals(new String[] { "hello", "world" }, result);
}
}Java Interfaces are also supported.
interface Calculator {
double plus(double a, double b);
double minus(double a, double b);
double multiplies(double a, double b);
double divides(double a, double b);
void noop();
}
QuickJS quickJS = new QuickJS.Builder().build();
try (JSRuntime runtime = quickJS.createJSRuntime()) {
try (JSContext context = runtime.createJSContext()) {
Calculator calculator = context.evaluate("" +
"a = {\n" +
" plus: function(a, b) { return a + b },\n" +
" minus: function(a, b) { return a - b },\n" +
" multiplies: function(a, b) { return a * b },\n" +
" divides: function(a, b) { return a / b },\n" +
" noop: function() { }\n" +
"}", "test.js", Calculator.class);
}
}Use TypeAdapter to support any type you like.
private static class AtomicIntegerTypeAdapter extends TypeAdapter<AtomicInteger> {
@Override
public JSValue toJSValue(Depot depot, Context context, AtomicInteger value) {
return context.createJSNumber(value.get());
}
@Override
public AtomicInteger fromJSValue(Depot depot, Context context, JSValue value) {
return new AtomicInteger(value.cast(JSNumber.class).getInt());
}
}
QuickJS quickJS = new QuickJS.Builder().registerTypeAdapter(AtomicInteger.class, new AtomicIntegerTypeAdapter()).build();
try (JSRuntime runtime = quickJS.createJSRuntime()) {
try (JSContext context = runtime.createJSContext()) {
AtomicInteger atomicInteger = context.evaluate("1", "test.js", AtomicInteger.class);
assertEquals(1, atomicInteger.get());
}
}QuickJS Android uses the similar APIs to QuickJS.
JSRuntime represents a Javascript runtime corresponding to an object heap. Several runtimes can exist at the same time but they cannot exchange objects. Inside a given runtime, no multi-threading is supported.
-- QuickJS Document
JSContext represents a Javascript context (or Realm). Each JSContext has its own global objects and system objects. There can be several JSContexts per JSRuntime and they can share objects, similar to frames of the same origin sharing Javascript objects in a web browser.
-- QuickJS Document
JSValue represents a Javascript value which can be a primitive type or an object.
-- QuickJS Document
Available subclasses of JSValue are JSNull, JSUndefined, JSBoolean, JSNumber, JSString, JSObject, JSArray, JSFunction, JSSymbol.
The original tests and benchmarks of QuickJS are in android-test. It's a console-like app running all tests and benchmarks at startup, like make test.