226d20e680 | ||
---|---|---|
classfile | ||
java | ||
tests | ||
.gitignore | ||
LICENSE | ||
Makefile | ||
README.md | ||
arrays.js | ||
classes.js | ||
classinfo.js | ||
context.js | ||
frame.js | ||
index.html | ||
jvm.js | ||
long.js | ||
main.js | ||
native.js | ||
opcodes.js | ||
signature.js | ||
timer.js | ||
util.js | ||
vm.js | ||
zipfile.js |
README.md
j2me.js
j2me.js is a small J2ME virtual machine in JavaScript.
A few similar projects exist. My primary objective is to keep this very simple and small and to leverage the CDLC JDK. In particular I am trying to implement as little as possible in JavaScript, re-using as much of the CDLC infrastructure and existing Java code as I can.
The VM core itself is based on node-jvm, which has a very nice classfile parser but is quite buggy and incomplete.
A few other projects like js2me.js exist, but they tend to implement the class library in JavaScript which is a bad idea because its a lot of work, and really hard to get right from a compatibility perspective (Java has a lot of quirks and poorly documented edge cases).
The VM is able to execute a "Hello World" Java program, which if you know anything about the Java bootstrap sequence, is quite complex.
To try this at home run the Makefile in java/ to generate the the class library jar (which is decompressed on the fly in JavaScript, using zip.js) and then load index.html in the browser (full disclosure: I only tried this in Firefox).
I will likely add some test automation in node.js next.