Declaration blocks can be used for static final blocks when the constant String or Objects are used repeatedly. Othewise declaration block is an even if not used properly.
I don't think that we need to use dynamic include everywhere. Most of the times we should try to use the static include only for the performance reasons as that block or file is included at the compilation time only and JSP engine does not have to include the block at the request time. If the resource is dynamic, dynamice include acts on a request and sends back a result that is included in the JSP page and then only JSP container resumes the processing of JSP page. -ShriKant A mailing list about Java Server Pages specification and reference wrote: > Until now I found only one place I can use it. It's an admin page where I > am > monitoring our server's current memory usage and memory usage "delta" > between two "events". > There you need some kind of "local", "static" (in C++ terms) variables to > keep track of previous/current memory usage and I found <%! %> a good > shortcut for doing it. > > I think it's enough for a programmer to look into the servlet code > generated > by a jsp compiler to really understand what the JSP spec means by > "Declaration". For a webdesigner, it's hard to avoid the confusion, so you > 're right, they shouldn't use <%! %> at all. > > What would you prefer to call this "declaration" instead? "JSP Class Member > definition"? > > david > -----Original Message----- > From: A mailing list about Java Server Pages specification and reference > [mailto:[EMAIL PROTECTED]]On Behalf Of Geert Van Damme > Sent: Wednesday, January 09, 2002 7:48 AM > To: [EMAIL PROTECTED] > Subject: Re: I want to make code shorter. > > > lol.. u sound like u have had a bad experience with declaration blocks :) > > Absolutely. I've seen too many people use <%! %> tags to declare variables > e.g. > It was absolutely a stupid move of the people who wrote the JSP specs to > call <%! %> a 'declaration'. I know what they mean and in some way they are > correct, but it is easil misunderstood. > e.g. I read an article in java developers journal (which is supposed to be > one of the biggest about Java isn't it?) about JSP-JDBC. For 1 it's a bad > thing to do your JDBC code inside a JSP itself, but ok, I can live with > that. > The trouble was that in this article he used code like: > <%! Connection conn = null; > Statement stmt =null; > ResultSet rs = null; > %> > bla bla > <% conn = getConnection ... and all JDBC stuff > %> > > Now listen everybody: DON'T EVER DO THIS !!!!!!!!!! > Don't declare variables in a 'declaration' (I know, there are exceptions, > but for now, simply DON'T ;-)! > ..... > > > Everyone should know what the difference between > > scriplets/declarations/and > > expressions is. > > If your not a newbie and you dont know exactly what a declaration block > is > > then you shouldnt be coding JSP pages. > > (sorry if that sounded rude. it's early and i cant think of a more > tactful > > way to say that) > > No, you're wrong ;-) > No matter what you say, JSP will always be used by newbies (now I think > about it, every technology, especially new technology, will always be used > by newbies, won't it?). > It's much more important that newbies get clear and correct information > like > (sorry if I repeat this quite often ;-), I think it's necessary) DON'T USE > DECLARATIONS AT ALL !!!!! > > It's only natural that JSP will be used by the more intelligent > webdesigner. > people that knwo the basics about making dynamic pages, they know what if () > for and while() is about, but don't completely get OOP or the servlet > model. > > Geert Van Damme > > =========================================================================== > 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
