From: JSPBuzz Vol I: Issue 3 -- 8/19/2000 HTTP://WWW.JSPInsider.com/ .
http://www.jspinsider.com/jspbuzz/2000/buzz_08_15_2000.view * Significant performance trade-offs exist for the various object storage options. -An array is at least 4 times faster than an ArrayList. -An ArrayList is at least 50% faster than using a Vector. -Don't use Vectors or Hashtables! Using a Vector or Hashtable will just slow your code down and give you a headache due to synchronization issues. -A HashSet is faster than a TreeSet (but both are much slower than an ArrayList) This is a bit outdated and the best thing to do will be to prototype different options. The rest of the article is very interesting for jsp performance as well so plz read it :) -Tim -----Original Message----- From: Ketharinath Kamalanathan [mailto:[EMAIL PROTECTED]] Sent: Monday, December 10, 2001 11:54 AM To: [EMAIL PROTECTED] Subject: Re: A JSP doubt I generally use Vector. I see Storage optimization here. Some useful code for you. Vector dbcvec = new Vector(); try { ResultSetMetaData rsmd = rs.getMetaData(); int numofcols = rsmd.getColumnCount(); int colcount = 0; Integer numcols = new Integer(numofcols); String[] colnames = new String[numofcols]; String[] coltype = new String[numofcols]; dbcvec.add(numcols); while(colcount<=(numofcols-1)) { colnames[colcount] = rsmd.getColumnName(colcount+1); dbcvec.add(rsmd.getColumnName(colcount+1)); coltype[colcount] = rsmd.getColumnTypeName(colcount+1); dbcvec.add(rsmd.getColumnTypeName(colcount+1)); colcount++; } dbcvec.add("DATA"); colcount = 0; while(rs.next()){ while(colcount<=(numofcols-1)) { // System.out.println(colnames[colcount]); dbcvec.add(rs.getObject(colnames[colcount])); colcount++; } colcount=0; } dbcvec.add("EOF"); /Ketharinath Kamalanathan ----- Original Message ----- From: "Praveen Potineni" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, December 10, 2001 10:45 AM Subject: Re: A JSP doubt > Hi Ketharinath, > I was also doing something similar. Can you suggest which collection objects > we can use to store values coming out of database and then send it to the > JSP. Can you elaboreate. Can you provide code snippets if you could. > Thanks > Praveen > > ----- Original Message ----- > From: "Ketharinath Kamalanathan" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Monday, December 10, 2001 11:35 AM > Subject: Re: A JSP doubt > > > > Hello Joshy: > > > > The ResultSet object needs a database connection to be maintained. You > > cannot access the ResultSet object without persistent Connection. So, when > > you have the ResultSet in the JSP you are trying to have the connection to > > the database. By this you are hogging the bandwidth and also suing more of > > your database resources. > > > > Its a fairly good idea to do the iteration in the Java Class then have > some > > collection object passed to the JSP. This eliminates the problems that I > > have mentioned about previously. > > > > Hope this helps. > > > > /Ketharinath Kamalanathan > > ----- Original Message ----- > > From: "JOSHY MON M C" <[EMAIL PROTECTED]> > > To: <[EMAIL PROTECTED]> > > Sent: Monday, December 10, 2001 2:34 AM > > Subject: A JSP doubt > > > > > > > Hi folks, > > > > > > Please answer my following questions > > > 1 .Is it a good practice to use the Resultset object directly on a JSP > > page > > > ? ( eg: for iterating employee recordet and displaying employee list ) > > > > > > 2. Instead, if I iterate the same recordset in a Jave class and make a > > List > > > of Employee object and return back to the page. Will it be a good > design. > > > How is it going to affect the performance. > > > > > > Please reply soon. > > > > > > Regards > > > Joshy > > > > > > > > > =========================================================================== > > > 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 > > > > =========================================================================== > 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 =========================================================================== 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
