i use a 2-dimensional array. i have a bean to which i send the query, the query is processed by the bean, stored in an 2-d array, and the array is stored as an object in a hashtable which is returned to the calling jsp/servlet where i iterate thru the 2-d array and get the results. its working pretty ok but u have tro b careful about null pointer exceptions. anyone with any suggestions on this?
***************************************** Amit Wadhwa Technical Support Representative, Dell International Services, Bangalore ***************************************** -----Original Message----- From: Hans Bergsten [mailto:[EMAIL PROTECTED]] Sent: Tuesday, November 19, 2002 10:47 AM To: [EMAIL PROTECTED] Subject: Re: Use of Vectors in JSP Deepak wrote: > Hi all > > Would you recommend the use of Vectors in jsp pages to hold the query results > from a database? > > Is it ok then performance wise to iterate over the vector and display the > items in the jsp page? > > For example, a method in a javabean executes a jdbc statement that returns > some recordsets. These recordsets are added to a Vector and the Vector is > returned by the method. > > In my jsp page I get the Vector with recordsets from the bean method. > Then I iterate over the Vector to display its items in a html table. > > Is this a good way of doing things? > If not can anyone suggest a better way? The methods in Vector are synchronized, so a List or an array is a slightly more efficient approach. But I would suggest that you look at JSTL instead. It's <sql:query> action exposes the query result as a type called a Result. From a Result, you can get an array of arrays where the first dimension represents rows and the second the column value, or as an array of Maps where each Map represents a row, with keys matching column names. Even if you access the database in servlet code (for instance), you can use utility methods to convert a JDBC ResultSet to a JSTL Result. For more info, see: <http://java.sun.com/products/jsp/jstl/> Hans -- Hans Bergsten <[EMAIL PROTECTED]> Gefion Software <http://www.gefionsoftware.com/> Author of O'Reilly's "JavaServer Pages", covering JSP 1.2 and JSTL 1.0 Details at <http://TheJSPBook.com/> ======================================================================== === To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST". For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST". Some relevant FAQs on JSP/Servlets can be found at: http://archives.java.sun.com/jsp-interest.html http://java.sun.com/products/jsp/faq.html http://www.esperanto.org.nz/jsp/jspfaq.jsp http://www.jguru.com/faq/index.jsp http://www.jspinsider.com =========================================================================== To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST". For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST". Some relevant FAQs on JSP/Servlets can be found at: http://archives.java.sun.com/jsp-interest.html http://java.sun.com/products/jsp/faq.html http://www.esperanto.org.nz/jsp/jspfaq.jsp http://www.jguru.com/faq/index.jsp http://www.jspinsider.com
