CMIS / CloudMist

[Florent Guillaume <fg...@nuxeo.com>]

Hi all,

I've done further work on a CMIS Java API implementation, now  
committed in a tentative "Apache CloudMist" project.
It's available as a Mercurial repository at:
   http://hg.nuxeo.org/sandbox/apache-cloudmist
You can see the main interface at:
   http://hg.nuxeo.org/sandbox/apache-cloudmist/file/default/cloudmist-api/src/main/java/org/apache/cloudmist/Connection.java
and browse the rest at:
   http://hg.nuxeo.org/sandbox/apache-cloudmist/file/default/cloudmist-api/src/main/java/org/apache/cloudmist/

There will be some controversial choices I'm sure, I'd be happy to  
explain and discuss them. Here are a few important points:

1. This API has to play two roles, the first is to be a simple API for  
the Java developer, which won't want to bother with low-level protocol  
concepts and want things to just work. The second role is to be a kind  
of SPI so that it can be used to implement a generic client layer or a  
generic server layer. This dichotomy leads to several signatures for a  
number of the Connection methods for instance.

2. I chose to have two classes representing objects: Entry and  
CMISObject.
Entry is the class that wraps whatever information was returned from a  
query or a getChildren etc. listing. It contains mainly getters, and  
hold mostly only the information that was requested. That's the class  
that the SPI part of the API will use, or that users interested in  
performance (e.g., in a listing of thousands of objects get only the  
title and modification date) will use.
On the other hand, CMISObject (and its four subclasses Document,  
Folder, etc.) are "live" objects and will fetch whatever properties  
are not already there, and they also have setters and more utility  
methods.

Today and tomorrow I'll be refactoring the current jcr-cmis code to  
use this abstraction layer in the middle, and work more on the AtomPub  
bindings part. In parallel, we'll be using this API internally at  
Nuxeo for other CMIS-related projects (clients, servers).

Please keep in mind that this isn't release code, and the goal is to  
tweak and polish this API until it is perfect :) A number of things  
are missing today I'm sure (one of them being thrown exceptions), they  
are probably just omissions, please don't hesitate to ask.

I'd welcome feedback on this, especially as I'll be submitting this  
code as a patch for the current jcr-cmis code as soon as the  
refactored code has equivalent functionality as today.

Thanks,
Florent

-- 
Florent Guillaume, Head of R&D, Nuxeo
Open Source, Java EE based, Enterprise Content Management (ECM)
http://www.nuxeo.com   http://www.nuxeo.org   +33 1 40 33 79 87