JavaScriptIsolate

public void addOnTerminatedCallback(@NonNull Consumer<TerminationInfo> callback)

Add a callback to listen for isolate crashes.

This is the same as calling addOnTerminatedCallback using the main executor of the context used to create the JavaScriptSandbox object.

public void addOnTerminatedCallback(
    @NonNull Executor executor,
    @NonNull Consumer<TerminationInfo> callback
)

Add a callback to listen for isolate crashes.

There is no guaranteed order to when these callbacks are triggered and unfinished evaluations' futures are rejected.

Registering a callback after the isolate has crashed will result in it being executed immediately on the supplied executor with the isolate's TerminationInfo as an argument.

Closing an isolate via close is not considered a crash, even if there are unresolved evaluations, and will not trigger termination callbacks.

@RequiresFeature(name = JavaScriptSandbox.JS_FEATURE_CONSOLE_MESSAGING, enforcement = "androidx.javascriptengine.JavaScriptSandbox#isFeatureSupported")
public void clearConsoleCallback()

Clear any JavaScriptConsoleCallback set via setConsoleCallback.

Clearing a callback is not guaranteed to take effect for any already pending evaluations.

public void close()

Closes the JavaScriptIsolate object and renders it unusable.

Once closed, no more method calls should be made. Pending evaluations will reject with an IsolateTerminatedException immediately.

If isFeatureSupported is true for JS_FEATURE_ISOLATE_TERMINATION, then any pending evaluations are terminated. If it is false, the isolate will not get cleaned up until the pending evaluations have run to completion and will consume resources until then.

Closing an isolate via this method does not wait on the isolate to clean up. Resources held by the isolate may remain in use for a duration after this method returns.

@RequiresFeature(name = JavaScriptSandbox.JS_FEATURE_EVALUATE_FROM_FD, enforcement = "androidx.javascriptengine.JavaScriptSandbox#isFeatureSupported")
public @NonNull ListenableFuture<String> evaluateJavaScriptAsync(@NonNull AssetFileDescriptor afd)

Reads and evaluates the JavaScript code in the file described by the given AssetFileDescriptor.

Please refer to the documentation of evaluateJavaScriptAsync as the behavior of this method is similar other than for the input type.

This API exposes the underlying file to the service. In case the service process is compromised for unforeseen reasons, it might be able to read from the AssetFileDescriptor beyond the given length and offset. This API does not close the given AssetFileDescriptor.

Note: The underlying file data must be UTF-8 encoded.

This overload is useful when the source of the data is easily readable as an AssetFileDescriptor, e.g. an asset or raw resource.

public @NonNull ListenableFuture<String> evaluateJavaScriptAsync(@NonNull String code)

Evaluates the given JavaScript code and returns the result.

There are 3 possible behaviors based on the output of the expression:

• If the JS expression evaluates to a JS String, then the Java Future resolves to a Java String.
• If the JS expression evaluates to a JS Promise, and if isFeatureSupported for JS_FEATURE_PROMISE_RETURN returns true, the Java Future resolves to a Java String once the promise resolves. If it returns false, then the Future resolves to an empty Java string.
• If the JS expression evaluates to another data type, then the Java Future resolves to an empty Java String.