First, see my previous reply to Margaret about what the user is going to request. It's a JSP page, not a call to a servlet.
However, your second point about letting the JSP do the DB access is closer to what I need, but it doesn't allow me (I think) to do the loads in parallel. I have to load Table 1, render the table, load Table 2, render the table, then render Table 1 again as a chart. Table-1-load and Table-2-load are serial, not parallel. What I'd like to do is simultaneously kick-off both Table 1 and Table 2 loads in the controller servlet. Then, when the last one finishes, forward to the JSP with the minimum set of data beans, and let the rendering take place. The more I discuss this on the list, the more I'm convinced that I need to parse the JSP. But I'm still open to suggestions otherwise. :) Jay > -----Original Message----- > From: David Mossakowski [mailto:[EMAIL PROTECTED]] > Sent: Thursday, April 25, 2002 3:09 PM > To: [EMAIL PROTECTED] > Subject: Re: Model 2 questions > > > No, you don't have to. When you make a request to display a table do > you not send as parameters which table to display, to the > servlet? Like > GET /servlet/GetTables?table1=yes&table2=yes > > You obviously have to have this info somewhere. I suspect > that you have > it in the JSP page and you think that you have to have all the data > ready in the bean so that it gets displayed. This is not true. The > TableList bean can get the data on its own when asked for it. > So in my > example the call to get a table from TableListBean would > actually go out > to the database to get that data. Next time the same table is called > for it would use the data that it already got for this request. > > The flow would go like this > GET /displayTables.jsp > > useBean TableListBean > > JSP wants to display Table 1 as an HTML table > > JSP calls TableListBean.getTable(1); > > TableListBean connects to DB and gets the data and returns it to JSP > > JSP renders the chart as HTML table > > JSP wants to display Table 2 as HTML table > > JSP calls TableListBean.getTable(2); > > TableListBean connects to DB and gets the data for Table 2 > > JSP renders Table 2 as HTML > > JSP wants to render Table 1 as JPG > > JSP calls TableListBean.getTable(1) > > TableListBean doesn't connect to DB because it already has this table > > JSP renders this table as JPG > > d. > > Jay Burgess wrote: > > > Unfortunately, if I understand your suggestion correctly, > then I've got to > > load every single table in my database as a bean, in case a > given JSP might > > need one or more of them. Since this could theoretically > be terabytes of > > data, I don't believe that solution would work. > > > > I think I've convinced myself that since the only way I can > know which > > tables a given JSP needs is to read the JSP in the > controller, so I'm going > > to have to go that route. > > > > (If someone can show me another way, or show me a flaw in > my thinking, > > that'd be great too.) > > > > Jay > > > > > -----Original Message----- > > > From: David Mossakowski [mailto:[EMAIL PROTECTED]] > > > Sent: Thursday, April 25, 2002 2:30 PM > > > To: [EMAIL PROTECTED] > > > Subject: Re: Model 2 questions > > > > > > > > > Your first question has been answered nicely already. > > > > > > As for the second I would suggest for you to have a > > > TableListBean where > > > you would put two TableBean instances one representing > Table 1 and the > > > other representing Table 2. Then in JSP you will use > the TableBean > > > representing Table 1 twice and the other once. > > > > > > The TableList might be implemented by using names to store > > > TableBean or > > > indexes. > > > > > > d. > > > > > > Jay Burgess wrote: > > > > > > > (I got no replies on the JSP list to these questions, so I > > > thought I'd try > > > > here...) > > > > > > > > In the Model 2 architecture: > > > > > > > > (1) Is there a difference between having the controller > > > servlet store the > > > > "model" beans in the Request or the Session before > > > forwarding to the JSP? > > > > Is one better than the other, or preferred from some reason? > > > > > > > > (2) How am I supposed to handle the case where the > bean(s) that the > > > > controller servlet is supposed to instantiate are > > > determined by the tags > > > > that are present in the requested JSP? Does the servlet > > > have to open and > > > > parse the JSP somehow in this case? As an example: > > > > > > > > Assume I have 2 custom tags, one that displays the data > > > from a database > > > > table as an HTML table, and one that creates a .JPG chart > > > image of table > > > > data. > > > > > > > > If Page1.jsp contains three tags ("show Table 1 as a > > > chart", "show Table 1 > > > > as a table", and "show Table 2 as a table"), then I'd like > > > to load Table 1 > > > > data into one bean, Table 2 data into a second bean, and > > > then forward to > > > > the JSP and let the custom tags do their drawing and > > > charting with the two > > > > beans. This is most efficient, as I'm only requesting data > > > for Table 1 > > > > once, even though it's being used twice in the JSP. > > > > > > > > But in this scenario, how can my controller servlet > determine which > > > > table(s) it needs to create beans for from the database? > > > > > > > > Jay > > > > > > > > > > > ______________________________________________________________ > > > _____________ > > > > To unsubscribe, send email to [EMAIL PROTECTED] and > > > include in the body > > > > of the message "signoff SERVLET-INTEREST". > > > > > > > > Archives: > > http://archives.java.sun.com/archives/servlet-interest.html > > > Resources: > http://java.sun.com/products/servlet/external-resources.html > > > LISTSERV Help: http://www.lsoft.com/manuals/user/user.html > > > > > > > > > > > > > > > -- > > David Mossakowski [EMAIL PROTECTED] > > Instinet Corporation 212.310.7275 > > > > > > > > > ************************************************************** > ***************** > > > > <<Disclaimer>> > > > > This message is intended only for the use of the Addressee and > > may contain information that is PRIVILEGED and/or > > CONFIDENTIAL or both. > > > > This email is intended only for the personal and confidential use > > of the recipient(s) named above. > > > > If the reader of this email is not an intended recipient, you have > > received this email in error and any review, dissemination, > > distribution or copying is strictly prohibited. > > > > If you have received this email in error, please notify the sender > > immediately by return mail and permanently deleting the copy > > you received. > > > > Thank you. > > > > > ************************************************************** > ***************** > > ___________________________________________________________________________ To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff SERVLET-INTEREST". 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