RSS feed for site updatesComparison of JSAdapter and JOMP
This is a comparison of JSAdapter and JOMP, two approaches to add metaprogramming features to Rhino.
JSAdapter
- Inheritance not as easy as with plain JS objects. Normal use needs wrapped object, but for prototype use in inheritance chain we need unwrapped adaptee object. As a result we need separate constructors/factory methods for the wrapped and unwrapped object, or wrap the object manually.
- getDefaultValue is forwarded to the adaptee object, so a toString() that relies on adapter functionality won't work. This is rather easy to fix.
JOMP
- Adds overhead to all property access methods of the default JS object.
- Not thread-safe. Making it threadsafe would probably require using a java.lang.ThreadLocal to disable the metaobject during invocation, which would put an even bigger burden on the default JS object.
Test code
This is a script that implements a base and extended object using both techniques, and a patch for adding JOMP support to Rhino.| name | type | size |
| TestObject.js | undefined bytes | |
| metaobject.patch | undefined bytes |