All,
I am new to this group. I just started learning Java. I have an
algorithm to impement in Java. I am having problems using Java. Can any
one help me to code this in Java.

I noticed some classes have "<E>" and "?".  What does it mean?
e.g:
public class TreeSet<E>
    extends AbstractSet<E>

I've got a question about JFrames. In a UI I created I have a button
which launches JFrames (actually they are extentions of JFrame:
ResizeFrame), each of which has the same name: 'jf'. Each JFrame
contains a panel - which is in turn displays an Image. The JFrames can

How can I calculate number of days between two dates?

I want to convert the String "2001-09-07 00:00:00.0" into the format
"09/07/2001".  How do I do that without having to do a bunch of string
manipulations?  Can I use SimpleDateFormat to just convert it to a
string?  I have tried that, but an error comes back saying something

how to make a executable jar files

what is the difference between newsserver and newsgroup ?
can i use mysql as a backend for a newsserver ?
what are the advantages of developing the
newsserver using jsp/servlets ?

what hardware do I need to simulate 500 HTTP vusers using Grinder ? I'm
asking about load generator machines. Does anyone have any experience
with that ?
Best Regards,

I am trying to determine why this code snippet returns a negative
boolean, when I've visually validated that the file does indeed exist?
Thanks, Scott
import java.io.File;

I have JTabledPane in my application. In it I have some tabs with titles
"Tab 1", "Tab 2" and "Tab 3". I want to have the color of the title "Tab 3"
is red (so it is easy to recognize). Is it possible?. Could you please
help..

1. In my struts-config.xml I use a form bean of type DynaValidatorForm
with some properties.
2. In the validator.xml I defined these fields as required.
3. I DO NOT WANT TO WRITE ANY ACTIONFORM CLASS

A Struts web application we are developing occasionally displays a
page (not a particular page) with no styles applied. The second
request for the same page always has the stylesheet applied. We are
using a separate stylesheet. I noticed that when this happened once,

I want to detect the version of the JVM that is being used by the
browser, for both IE & Firefox (and maybe also Opera & Safari if
possilbe).
I have searched around the web for such a program, however it seems

I was just wondering if a java function is able to modify variables
that are passed to it.
I want to create a function that I can pass 3 x, y, and z variables to
and have the function set them to a certain point.  Does anyone know

I have a simple quesion... What is a better solution for desktop
application: to retrieve the data from DB whenever i need something, or
just instantiate an object containing all the data I need (lets say a
collection of 70 String objects, some ints...)?