Client-side templating language with java compiler as well (DRY templating)

I want to be able to define templates once and use them to render html from both the server-side as well as the client-side. (DRY principle and all that)

The API that I'm envisioning is simply this: render(JSON, template) --> html.

I'm using a java-framework (actually Play framwork, but I don't think this is framework specific).

I've read a lot of similar questions, the latest, and most helpful being: Templating language for both client-side and server-side rendering.

I pretty much agree with the author that obvious contenders like: Mustache and Google Closure Templates are not going to cut it. (for reasons see that post)

Requirements:

• MUST: client-side rendering
• MUST: client-side caching of template-files
• NICE: client-side 'compile-once execute many times' of template-file to fast javascript-code
• MUST: server-side rendering
• NICE: native java implementation

I've seen a bunch of posts suggesting the use of Node.js for server-side templating. Although this would definitely work (underscore templates, Handlebarsjs, EJS would all work just fine) I'm struggeling 开发者_开发问答to see how to communicate/combine/integrate Node.js with java, after all it's still the java framework that needs to output the JSON

I've seen posts mentioning some proof-of-concept communicating between a JVM and node.js (over http or using JNDI) . However, no library, let alone battle-tested, seems to be available at the moment.

So to round things up, what client-side templating engine would you suggest that would run in java as well (or with some hoops, can be called from a jvm) ? And if that 'hoop' happens to be Node.js, what ways of communication/ library would you suggest to use?

I'm going for Mustache for now and anticipating a java implementation for Handlebars.js. Once that exists, the refactoring-path shouldn't be that steep.

EDIT - april 2012

Ok, updating this for future reference:

• I'm outsourcing server-side templating to Node.js.
• communication between java and node.js implemented using sockets. (see: Sending data from node.js to Java using sockets for where I got the idea)
• Since now I only need a client-lib (or better one that runs in javascript on both client and server-side using node) I can choose more freely. Having become accustomed to Mustache, I've chosen the Hogan parser (by the Twitter guys) ( http://twitter.github.com/hogan.js/ )

100% DRY (even the client-side mixins and i18N-bundles come from the same source. Moreover, Hogan can precompile the templates server-side and open a connection to the client so the client doesn't have to parse the template anymore on first connect.

Is it fast? Lightning...