Error with paging action handler

Question

We are using the proposed action handler from Steve Muench's book for stateless paging to our highest confidence.
The problem is that after some days the paging parameter p gets always a wrong value. We think it is the total rowcount, because we implemented a test-parameter.
From then displaying a page starts always (?) with the last page. If this situation occurs it happens in different (!) applications, so it isn't a parameter side effect.
There is not p session or cookie parameter who could override the silent work of the action handler.
We are using the XSQL servlet 1.0.4.1 under Red Hat Linux 7.0 with an Oracle 8.1.7 database. Servlet container is Tomcat 3.2 with JDK 1.3 from Sun.
Stopping Tomcat and restarting it solves the problem (for some time).
Do you have any hint for us ?
Best regards
Andreas Saake
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Answer 1

As I can see it's an error from Paging.jar.
I do an initial call to a XSQL page with a select resultset of 38 rows, for example. With a pagesize of 20 rows I should get 2 pages and having current-page set to 1.
But what I get is a corrected value (by Paging.jar) of current-page, which starts with page 2. The further paging in my application is ok.
I've extended the paging handler with a variable called test-paged, which reads the paramater p and stores it in the output tree. Then I dislay the XSQL-page without any stylesheet and get a value of 38 in test-page.
Below is an excerpt of my paging.jar:
---- Start excerpt
import oracle.xml.xsql.*;
import oracle.xml.parser.v2.*;
import org.w3c.dom.*;
import java.net.*;
import java.util.StringTokenizer;
import java.sql.SQLException;
public class Paging extends XSQLActionHandlerImpl {
private static final String PAGE_PARAM_NAME = "p";
private static final String ROWSPERPAGE = "rows-per-page";
private static final String TARGETPAGEARGS = "url-params";
private static final String TARGETSORTARGS = "sort-params";
public void handleAction(Node root) throws SQLException {
XSQLPageRequest req = getPageRequest();
Element actElt = getActionElement();
// Get the count query from the action element content
String query = getActionElementContent();
// Get the number of rows per page, defaulting to 10
long pageSize = longVal(getAttributeAllowingParam(ROWSPERPAGE,actElt),10);
long totalRows = longVal(firstColumnOfFirstRow(root,query),0);
long curPage = longVal(variableValue(PAGE_PARAM_NAME,actElt),1);
long testPage = longVal(variableValue(PAGE_PARAM_NAME,actElt),1);
// Get the name of the current page to use as the target
String pageName = curPageName(req);
// Get any URL parameter names that need to be echoed into paging URL's
String pageArgs = getAttributeAllowingParam(TARGETPAGEARGS,actElt);
// Get any URL parameter names that need to be echoed into paging URL's
// FOR SORTING
String sortArgs = getAttributeAllowingParam(TARGETSORTARGS,actElt);
// Calculate the total number of pages
long totalPages = totalRows / pageSize;
long fract = totalRows % pageSize;
if (fract > 0) totalPages++;
// Make sure current page is between 1 < cur < totalPages
if (curPage < 1) curPage = 1;if (curPage > totalPages) curPage = totalPages;
// Create the <paging> fragment to add to the "data page"
Document d = actElt.getOwnerDocument();
Element e = d.createElement("paging");
root.appendChild(e);
addResultElement(e,"total-rows",Long.toString(totalRows));
addResultElement(e,"total-pages",Long.toString(totalPages));
addResultElement(e,"test-page",Long.toString(testPage));
addResultElement(e,"current-page",Long.toString(curPage));
--- END Excerpt
Thanks,
Andreas
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