Re: [JXPath] Plans for JNDI, JMX and Filesystems?

[Brian McCallister]

You may be right. An important thing to keep in mind in O/R mapping, 
though, is that you very rarely  need to do a join in the query (I have 
yet to have to do one in six+ projects I have worked on using OJB) as 
most joins are mapped as properties (collections) on other objects. 
Hierarchical semantics make a lot of sense when querying into what is, 
to the client, just an object graph.

-Brian

On Jan 3, 2004, at 2:44 PM, Dmitri Plotnikov wrote:

In my opinion, XPath is much too weak of a query language for 
relational
databases. What you want is something like XQuery, which is a superset 
of
XPath that includes relational semantics a la SQL.

I wonder if there is an open source project similar to JXPath, but with
XQuery as the base language.  I looked at the SourceForge project 
called
JXQuery.  Very interesting, but it does not appear to have ambitions 
beyond
XML applications. Did I misunderstand?

Mapping of XPath semantics to Java objects is a highly contraversial 
issue -
when I was building JXPath I had to make many decisions on that front 
that I
myself was not very comfortable with.  I can only imagine the 
magnitude of
this problem if we try to map XQuery to arbitrary object models.  Can
anybody see an easy solution there?

- Dmitri

----- Original Message -----
From: "Brian McCallister" <[EMAIL PROTECTED]>
To: "Jakarta Commons Users List" <[EMAIL PROTECTED]>
Sent: Friday, January 02, 2004 11:15 PM
Subject: Re: [JXPath] Plans for JNDI, JMX and Filesystems?

I don't know about these, but I am trying to talk any of the JXPathers
into helping put together the ability to query persistent object 
models
via OJB (which will mean building OJB queries from JXPath AST's or
something)...

-Brian

On Jan 2, 2004, at 3:49 PM, Michael Nascimento Santos wrote:

Hey,

I just would like to know if there are any plans for JXPath to 
provide
special support for navigating JNDI, JMX and filesystems.

Thanks,
Michael
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]



---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]





---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]



---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]