General JSP Questions

Hi,
I work at a marketing company and here we still use Classic ASP, and now we're starting to learn and implement JSP on our projects.
We managed to get things working just like we do in ASP, however with just that I don't see any advantage at all, it's just that we currently are doing exactly the same thing we do with ASP, a form sends the user input to a code-page, we get all the parameters, insert/delete/update the DB, and return the user to another page. Everything's the same, except the language syntax that changed.
So this is what I'd like to ask, what are some common "best practices" of using the JSP technology?
As someone who's just started on JSP from ASP, what are the practical advantages?
(One of the advantages - or actually the only one I can think that really saves some time are the Beans)
Any sources/tutorials are welcome.
Thanks,
Daniel

DanCoelho wrote:
As someone who's just started on JSP from ASP, what are the practical advantages?
(One of the advantages - or actually the only one I can think that really saves some time are the Beans)None. JSP on its own is pretty useless.
The real power lies in the fact that you have a JVM available to you - in other words you can write and execute Java code. The trick is learning how to do this efficiently so that the web part isn't a bother, and that is where JSPs partly come into play.
The simplest of the simplest form of Java web development that is at least somewhat of a clean design is to combine Servlet and JSP technology. Servlets are simple java classes that can serve HTTP requests - generally you will use them to handle the business logic side of a request. Database queries, complex calculations and any other kind of data manipulation is done at this point - generally you'll write specific classes to actually do all the work, and you use those classes in your servlets.
What you do not want to do in Servlets is generate the view - the content sent back to the browser that the user will actually see. Generally this is HTML or XHTML content, but it could be something else entirely. JSPs, in combination with for example JSTL, are far better suited to fulfill this task. JSPs represent simple templates to massage data into page content, and the rule of thumb is that they are only correct when they contain absolutely no java code at all.
So the general flow of this is:
- user goes to your website or clicks on a link or a button. This will trigger a servlet.
- the servlet handles all the business logic that is required
- when the servlet is done, it forwards control to a JSP
- the JSP generates the view, based on data that was generated in the servlet
This may seem like a lot of work, but it really isn't once you get the hang of it. And there are still plenty of ways to make your life even easier still, using specific frameworks that exist such as Spring MVC or JavaServer faces.
Whatever choices you make, there is one thing that is true for all of them: before you can do anything in the Java web development world, you'll need to know core Java. Intimately.

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hello dreamweavers.
im a newbie going to use dreamweaver from next week and beyond,so id like to ask the following:
should i design the website in photoshop and then import it into dreamwevaer,in order to code it?
is dreamwevaer flexible in design point of view,or is it mostly getting finished designs such as headers,footers,flash banners,
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thank you.

Hello Nancy.
seems like an informative website,i can see it is easy to understand the
basics.
Στις 23 Μαρτίου 2012 4:29 π.μ., ο χρήστης Nancy O. <[email protected]>έγραψε:
Re: general dreamwevaer question created by Nancy O.<http://forums.adobe.com/people/Nancy+O.>in
Dreamweaver - View the full discussion<http://forums.adobe.com/message/4283588#4283588

Which forum should I use if I have JSP questions?

Hi, pals!
Which forum should I use if I have JSP questions?
Cheers,
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http://forum.java.sun.com/forum.jsp?forum=45

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Hi
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4) No.
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Regards
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Please rate helpful posts...

Javascript to JSP question...Can javascript function set session attributes

hello,
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hello there,
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you have an interesting tool. can i see?
i hope i wasn't too confusing, but your problem is sooo interesting. =)
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-Allen Wicks

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Can we use htmlb components in abstractportal components.
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Hi out there,
i'm using thoe following BADi: /SAPSLL/CTRL_SD0C_R3 (Global Trade Service).
But also, this question is a general question.
If we are calling on screen the transaction VF01, the BADi is called correctly.
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Timo
Edited by: Timo Ehl on Apr 14, 2009 7:27 PM

Hi,
generally BADIs are called in background mode. You can use the following trick to debug your BADI. You just need to create an infinite loop in your BADI implementation. Something like this.
DATA: l_a TYPE c.
WHILE l_a IS INITIAL.
ENDWHILE.
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I have a general OOP design question, and am wondering if someone could relate an answer to the following design?
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Voila! - the window appears. I WAS very proud of myself.
Now I want to access something inside the window. Specifically, there's a radio button that was created in createToolPanel(); - I want to update it to be selected or not selected when I receieve the user's preference from an xml settings file at start up (xml is loaded into the doc class).
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- do it the way I'm trying to, ie try to access the radio button directly from the doc class (which isn't working):
File_Folder_Import.myRadioButton.selected = true;
- a better way someone can briefly explain the concept of?
Another way to explain my design is...
- a bunch of different windows, each created by a different class
- xml file loads preferences, which need to be applied to different tools (radio buttons, check boxes, text fields etc) in the different windows
I read a lot of posts that talk about how public vars are mostly bad practice. So if you are making your class vars private, what is the best way to do the kind of inter-class communicating I'm talking about here?
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The main reason you want to use get/set functions is validation. You want your class to act properly if you send an invalid value. Especially if anyone else besides yourself is going to use the class. Plan for the worst.
The general concept is, make a private variable for any 'state' you want to remember using an underscore in the variable name to easily identify it as a private var, then make get/set functions with the same name with any required validation without the underscore.
e.g.
package
     public class MyClass
          // property called 'mode' to track something with an int
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          public function set isChecked(modeVal:int):void
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Simple JSP question (newbie)

Hi all,
firstly I hope this is the right place to post this question, if not, please accept my apologies,
I am putting together my first set of JSP pages with Tomcat, and so far everything is going very well, but I am having one small problem.
I have 1 JSP page at the moment, and that in turn uses 1 JavaBean thing bit of code to do something.
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<%! int score; %>
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<%
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%>
<jsp:useBean id="converter" class="scoreApp.SaveScoreBean"/>
<jsp:setProperty name="converter" property="scoreToSave" value="${score}" /> As you might see, the problem comes in that last line of code - I want to pass the "score" integer I've received off to the bean, but I don't know the syntax for this. I've tried "value=score", "value="score"", "value="$score"", "value="${score}"" etc. but to no avail.
You can see this is a super-simple problem :)
... but my if it isn't becoming frustrating :)
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Many thanks,
Peter

technologyMan wrote:
I am learning jsp now. You´re actually at the JSF forum here.
Now, i am a textfield control on jsp as textField1. You are? Really?
I have created this control from Palette. in java code i am writing "textbox1." but there is no action, no intellisense while pressing ctrl + space.
How the control is accessing from java code? Maybe my logic with visual studio .net. but i want to learn jsp logic.Uh, just write code accordingly? You can use h:commandButton/h:commandLink for that.
Anyway, if you want to start with JSF, I can recommend you the following sources:
Java EE tutorial part II, JSF starts at chapter 10: [http://java.sun.com/javaee/5/docs/tutorial/doc/]
Good kickoff tutorial: [http://balusc.blogspot.com/2008/01/jsf-tutorial-with-eclipse-and-tomcat.html]
The JSF taglib documentation: [http://java.sun.com/javaee/javaserverfaces/1.2/docs/tlddocs/]
The JSF API documentation: [http://java.sun.com/javaee/javaserverfaces/1.2/docs/api/overview-summary.html]

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          I know that there is a "compile JSPs on deploy" option, but that's just not
          practical. Our site has almost 3000 JSPs, and the deploy would just be
          eternal. Worse, the system must "re-deploy" the application whenever WLS
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          Best Regards,
          Will Hartung
          ([email protected])


          Try to set working dir or similar in your weblogic.xml. You can use admin console
          to set/edit it and make the modified descriptors persistent.
          "Will Hartung" <[email protected]> wrote:
          >Hi all, a couple of questions.
          >
          >WLS 7.001 (think it 001, maybe 01, whatever, it has the first SP I'm
          >pretty
          >sure), on W2K (dev) and Solaris 8 (deploy).
          >
          >Currently our app is deployed in "exploded" form within WLS, for
          >developement, but will be deployed as a single EAR in production.
          >
          >Whenever we restart WLS, it seems to need to recompile the JSP as it
          >first
          >sees them, rather than taking advantage of the fact that they were compiled
          >"last time". Once compiled, the system seems pretty quick, but the JSP
          >compiles really crush any built up momentum.
          >
          >Is there a way around this? A way for it to not recompile "unchanged"
          >JSPs
          >after the sever is restarted?
          >
          >Second, what is the Best Practice on how to pre-compile the JSPs, so
          >this
          >can be eliminated completely. Does anyone have a good document on how
          >to
          >create a WAR filled with pre-compiled JSPs? Is there an ANT task that
          >only
          >pre-compiles the changed JSPs during a build?
          >
          >I know that there is a "compile JSPs on deploy" option, but that's just
          >not
          >practical. Our site has almost 3000 JSPs, and the deploy would just be
          >eternal. Worse, the system must "re-deploy" the application whenever
          >WLS
          >starts up, which means a recompile, and that's simply not practical.
          >
          >Thanx for any advice you can provide. (Yes, I know we have a lot of JSPs,
          >but that's not going to change soon...)
          >
          >Best Regards,
          >
          >Will Hartung
          >([email protected])
          >
          >
          >

Best Font for Subtitles? and other General Subtitling questions?

I've never had to use subtitles, until my current project, so I am looking for some general advice and suggestions.
I will be using PPCS3 (on XPpro) as the subtitles (as in the kind that translate a foreign language) will be permanent.
So here are my questions:
1. What is the best font and or what is the most standard font for subtitles? (Font size and other characteristics may be worth mentioning here too.)
2. Is it possible to have an outline around the text as opposed to shadow?
3. What are some general rules of thumb for subtitles that apply to broadcast and cinematic productions?
Thank you.

See also:
FAQ:Why are my titles blurry/wrong?
Cheers
Eddie
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Basic JSP question

Hi,
I'm starting to use JSP, and I have a few basic questions. I've found some tutorials online, such as the J2EE tutorial, and some others through Google, that have been helpful. However, after reading some tutorials, I still have a basic question:
If I have a Java class file, can I access that class' methods through my web page using JSP, and then retrieve information from that class?
For example, if I have a class MyClass, a method myMethod, and an ArrayList<String> arr, would I be able to do something like this from my web page?
MyClass.myMethod();
MyClass.arr.get(0);If anyone can give me some advice, or possibly link me to a tutorial that will explain this, I will be very appreciative.

Yes you can, here is a quick example of how you could do that.
<%@ page language="java" contentType="text/html"
pageEncoding="ISO-8859-1"%>
<jsp:useBean id="myObject" scope="session" class="mypackage.MyClass" />
<html>
<body>
<%
myObject.myMethod();
%>
<%= myObject.arr.get(0) %>
</body>
</html>

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