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From "Zachary Mitchell, BCIS" <zac....@internode.on.net>
Subject Re: custom Table
Date Tue, 24 Feb 2009 07:55:49 GMT
There are a few things to know with JSP's

and copies of objects in JSP's,

when it comes to variables of

session and page

scopes.

A text/ebook like "special edition using Java 2 enterprise edition

clarifies this, but it all goes to the fact that  a jsp deploys to its servlet engine

by being compiled into a servlet class/instance, which is injected

 and then executed from there.

This means that every client web browser run of the jsp

is running from THE SAME class of your programmed jsp,

though from different server threads and different browser

instances though.

You need to be careful that each page variable object

doesn't conflict with other objects by use of page objects.

You will want each to have a local copy of your resultset Object,

in each jsp page context, to be a unique object context, and each have all of 

them concurrently in your jsp, rather than be using dirty references back to your 

original copy.

It should (your resultset object), optmistically, be unbound from your resultSet Object produced
by

bean/corba/rmi/ejb/whatever object source.

In your example, in a situation where each jsp page

may alter it's unique resultset object later on,

-you may use a  managed class/bean/enterprise javaban 

to correspond to your entire table, to have setResultSet/getResultSet methods.  

These methods may have somethig like a linkedlist that holds resultset objects (or a complexresultset
object of yours, to include an id for each <TD> node.
This way, you have one managemenet class, and are blind to key objects,

and have a manager (Accessible) class.

>From hear, each page may the obtain it's own particular

pageContext copy of your resultselt object.

//******************************************************************************************


Or, you may use a  LinkedList object in an application scope, which of its own, is outside
of every page's context.

The page that get's a LinkedList<ResultSet> from there, the page deals 

appropriately with it's resultset, and may use the java.util.LinkedList

method to update the collection appropriately.

the page context.

See how ya go, but doen't overlook the reading I suggested,

even though your stuck, and it's old!

:)


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