This document surveys different JavaScript execution environments for Android applications: Anode, V8 via WebView, V8 via Zazl, Rhino, and a potential Java V8 bridge. It finds that Anode is no longer actively maintained. V8 via WebView has low performance due to single-threading. V8 via Zazl and Rhino are also no longer actively supported. A Java V8 bridge could provide high performance and stability by leveraging the V8 engine via JNI, though it would require more complex implementation.

1. JavaScript Execution
Environment Survey
2014.11.18.
KAIST IT융합연구소 한동균

2. Motivation
Instability of Anode
Inactive development of Anode
Structural defect of Anode application
Depending on external service call which is hard to
manage whole application
Implementation of native Java based cloudlet
platform is almost done

3. Motivation
App1
App2
Implement two applications which have
same behavior but in different language
Implemented in
Objective-C
Implemented
in Java

4. Motivation
App
One Source Multi Use
Implemented in
JavaScript

5. JS Execution Environment
Anode
V8(Webview)
V8(Zazl)
Rhino

6. Anode
https://github.com/paddybyers/anode
A port of node.js to the Android OS and libraries
Able to leverage web socket
Unstable execution environment
Not active development

7. Anode (cont’d)
node.js is ported by Paddy Byers
Anode is implemented by Paddy Byers
5 contributors on Github (including me)
Not in active development

8. V8 (WebView)
https://code.google.com/p/v8
Google’s open source JavaScript engine which is
written in C++ and used in Chrome.
V8 is the default JavaScript engine of Webkit
Since Webkit runs on UI thread, only one thread per
application, we cannot run multi-thread computation
leveraging WebView

9. V8 (WebView)

10. V8 (WebView)

11. V8 (Zazl)
http://www.zazl.org
Java based server-side JavaScript tools
Zazl contains V8 Java Bridge (i.e. Enable the use of
the V8 JavaScript Engine within Java)
Inactive development

12. Rhino
https://www.mozilla.org/rhino/
An open-source implementation of JavaScript
written entirely in Java.
Stable JavaScript computation
Since it is implemented in pure Java, it shows
relatively low performance than other JS engines.

13. Rhino (cont’d)
Implemented by Mozilla developers
Rhino is embedded in Java SE 6 and 7 as the
default Java scripting engine
Oracle has announced Nashorn as the default
JavaScripting engine in Java SE 8 (JSR-292)
However, Android does not support Java 8 yet.

14. Performance Comparison
http://ariya.ofilabs.com/2014/03/nashorn-the-new-rhino-on-the-block.html

15. Comparison Table
Approach Implemented Stability Maintainability Performance Complexity
Anode
C/C++(node.js)
with Java
low
no more
support
normal
high
(External
Service Call)
V8(WebView) C/C++ high
Officially
support
low
(Single Thread)
low
V8(Zazl)
C/C++ with
Java
high
no more
support
high low
Rhino Java high
no more
support
low
(Java
Implementation
)
low
Nashorn Java high not support yet high low

16. Java V8 Bridge
Leverage JavaScript V8 Engine in Java via JNI
It guarantees high performance, low complexity, and
high stability
Not familiar (JNI, Android NDK), but looks simple
http://www.zazl.org
http://lorinbeer.github.io/tutorial/2013/03/22/vatedroi
d-embedded-v8-in-android.html

17. Java V8 Bridge
C/C++
JavaScript V8 Engine
Java
JNI (Java Native Interface)
Android Application

18. Comparison Table
Approach Implemented Stability Maintainability Performance Complexity
Anode
C/C++(node.js)
with Java
low
no more
support
normal
high
(External
Service Call)
V8(WebView) C/C++ high
Officially
support
low
(Single Thread)
low
V8(Zazl)
C/C++ with
Java
high
no more
support
high low
Rhino Java high
no more
support
low
(Java
Implementation)
low
Nashorn Java high not support yet high low
V8 Bridge
C/C++ with
Java
high
support
ourselves
high low