In this article I cover the syntax for the new PB 8 exception handling, how
to write the exception handlers that will improve your code, as well as
issues concerning legacy code that currently implements exception-handling
strategies.
If you've used Java or C++ to develop software, you're probably well
acquainted with exception handling in those languages. If you're a
PowerBuilder programmer, you may be familiar with the way previous versions
of PowerBuilder handled exceptions in the SystemError event of the
application object.
One of the more common sources of PowerBuilder SystemErrors occurs in
relation to DataWindows. For example, this code is written in the clicked
event of a DataWindow control:
dw_1.getitemstring(row,2)
It appears harmless, but it's really a SystemError waiting to happen. The
error will occur when you click on the DataWindow control, but not ... (more)
I've heard it said that PowerBuilder isn't going to survive the competition
from other software development tools. I, like many of my friends who are
software developers, can't afford to ignore such rhetoric and I continually
upgrade my knowledge of other languages.
I'm impressed by Java and its simple way of doing some complex tasks and
enforcing object-oriented practices when writing code. One of the areas Java
makes simple is that of creating threads to run asynchronously while other
code is executing.
Recently I took an assignment to help a company upgrade their Sybase databa... (more)
In Part 1, "The Java DataWindow" (PBDJ, Vol. 9, issue 2), I examined the Java
DataWindow from the perspective of a classic client/server application that
used a direct JDBC connection to the database. In Part 2 I use the same
application source code and convert it to use EAServer connection caches for
indirect access to the database. By using EAServer connection caches, fewer
connections to the database are required, which can reduce costs.
In EAServer 4.0 is a simple tutorial, “Creating the Application”
(file:///D:/Program%20Files/Sybase/EAServer4.0/html/docs/jaggs/cookp11.htm#X1... (more)
I recently received a copy of PowerJ 4 for evaluation. As a PowerBuilder
developer turned Java developer, I was particularly interested in the Java
DataWindow. I had developed JDBC software using a Java control known as the
JTable, but I felt I was wasting time compared to what it took me to use the
DataWindow painter, create a SQL-based DataWindow object, and use the
DataWindow control to display it.
This article explores the Java DataWindow without the PowerJ GUI. To get a
licensed copy of the Java DataWindow, you'll need to purchase a copy of
PowerJ. But there may be times wh... (more)
Why use DHTML for the tab control when there's a Java tab control available?
The answer is that DHTML is much lighter, and we can minimize the "heaviness"
of the page by using it.
Last year I wrote an article on "EAS and DHTML Tab Controls" that appeared in
PBDJ (Vol. 7, issue 4). Developers have used tab controls for years, long
before the Internet was invented. But one of the problems with developing
GUIs in the browser is using HTML to give users the functionality they need.
DHTML is powerful, but it's not as powerful as traditional programming
languages and it tends to be cl... (more)
Tim Nesham, a consultant with BORN, has 14 years of experience in the IT industry. Having started with seven years of C programming experience, he later became a CPDP4 and certified PowerBuilder instructor.
David Lucas
Shaul Efraim
Terence Martin Breslin
Cory Marchand
David Hughes
James Carlini
John Iffert
Dan Stolts
Joe Zeto
