I have a JTable that I want to add a new column to every time someone
clicks a button.  I have been reading about extending the
AbstractTableModel, but I don't how this allows you to add a new
column.  The examples online show what happens when a user edits a

I think System is an object and in is one of System's fields. Can
someone give me a clarification?

I'm looking for an offset-based data structure to hold character data.
Background: I'm working with an app whose server is written in Java
while the client is in C. The server needs to package up a bunch of data
and ship it to the client where it will be traversed, read-only, ...

I'd like to know if we can do some user-level signal handling like those
provided in the Linux + C/C++?
What I would like to do is to capture SEGV fault signal (or to make it
simpler, null pointer exception) which can happen anywhere in the Java user

While I have been programming for many years, I have decided that I
need to start thinking more like a developer than a programmer.  As
such, I have been trying to improve my Java skills and OOAD skills.
One of the items I have run across in my self-education is the axiom

I have a class hierarchy where the constructor of a child class ("Ford")
can throw an exception, while the constructor of the parent class
("Car") has some side-effects.
If construction fails due to the Exception on the child class being

I am developing a web application to allow users setup a complete test
environment for their specific needs :-
        - hardware
        - users

My own position (and also what I've gathered in workshops
before my SCJP and also from reading this newsgroup) was,
that generally it is better to allocate and drop objects
inside a loop, rather than allocate them before the loop

Hi in the past i was using the followng code below to check if a
server was up and if it was to call a jsp...
However the jsp now resides to my server so there is no point really
of chekcing if it is up to call it ..

While "explain" works perfectly in mysql console, it does not print out
anything in java code. Is there any workaround?
selectCmd = " select * from ";
selectCmd += " t1";

I have the path of computer's sharing folder \\MS27\\masterroot. How
can I get the absolute path of this folder on that computer?

here is a method i writte in java
public void aaa(){
JFileChooser chooser=new JFileChooser();
chooser.setFileFilter(new FileFilter() {//

Does anyone have inside information on how much temporary memory Sun
Java 1.5 needs for heap compaction while using the CMS collector?  I'm
tuning new 16GB 64 bit Solaris systems where the Java heap is mostly
small objects.  If I shrink the Java heap too much, there's physical

I want to make my Java class Person only visible to other classes
located in the same package, invisible to other classes in other
packages. How should I do that?
By trying different keywords, I found one way is:

I have an excellent Internet project for entrepreneurship. But I am
not a technology-savvy guy. The requirement on technology is not that
hight if you are an experienced web programmer. Currently I have no
business plan. Because it is difficult for me to estimate size of the