Java Tech

In your face or under the hood, Java Tech is your guide to the what and how of Java technology. Each month, Jeff Friesen takes a look at the inner workings of Java, and how they can be used. From language and JVM features to handy techniques that will be front and center in your applications, you'll find a grab-bag of essential ideas and important facts in this column.

Java Tech: Process Images with Imagician
Jeff Friesen returns to image manipulation in the latest installment of "Java Tech," showing how to create an image-editing application with a series of common, useful graphic effects. He also adds a status bar that explains the effect of each menu item. Feb. 7, 2006

Java Tech: Image Embossing
Many GUIs use an "embossing" effect to create the illusion of depth, manipulating pixel colors to suggest small ridges and valleys. In this installment of "Java Tech," Jeff Friesen introduces an algorithm to perform the embossing effect, and shows how easy it is to implement with Swing and Java2D. Dec. 8, 2005

Java Tech: Generics and You
Are you ready to put your generics knowledge to the test? Java Tech columnist Jeff Friesen has compiled a quiz with 20 questions designed to dig deep into the concepts, features, and gotchas of this major J2SE 5.0 feature. Nov. 10, 2005

Java Tech: The Sweet Song of the BlueJ, Part 2
BlueJ, an IDE for beginning Java programmers, has more under the hood than you might expect. In the second part of his survey of BlueJ, Java Tech columnist Jeff Friesen looks at BlueJ's support for debugging, unit testing, building executable JARs, its configurability, and more. Aug. 30, 2005

Java Tech: The Sweet Song of the BlueJ, Part 1
It's hard to teach the object-oriented concepts of Java when the first thing the student sees is the very procedural public static void main (String[]). BlueJ offers a way to teach Java's OO concepts in a visual environment, allowing the student to connect and implement classes with mouse clicks and drags. In this installment of "Java Tech," Jeff Friesen introduces this educational tool. Jul. 21, 2005

Java Tech: Language Lessons
Java Tech columnist Jeff Friesen has been coding in Java for nearly ten years, and in that time, he's found some surprises in the language, like how += doesn't necessarily do what you expect, or the hazards of invoking a potentially overridden method in a constructor. In this article, he provides some important lessons based on this experience. May. 17, 2005

Java Tech: Acquire Images with TWAIN and SANE, Part 2
With his first JTwain library, Jeff Friesen got image acquisition working, but with limited functionality and many inefficiencies. In this installment of the series, he builds a better JTwain by introducing TWAIN "capabilities." Jan. 25, 2005

Java Tech: Acquire Images with TWAIN and SANE, Part 1
Java doesn't provide a standard API for acquiring images from devices like scanners and digital scanners, but there is a widely adopted standard, TWAIN, that can be called from native code. In this installment of Java Tech, Jeff Friesen shows how to bring that functionality to Java. Nov. 18, 2004

Java Tech: The ABCs of Synchronization, Part 2
Jeff Friesen's introduction to thread synchronization continues with a consideration of communication between threads, the use of volatile variables, and the new synchronization concepts introduced in J2SE 5.0. Sep. 15, 2004

Java Tech: The ABCs of Synchronization, Part 1
Java's thread support is powerful and comprehensive, but it can also lead to problems if you don't fully understand what you're doing. In his latest Java Tech column, Jeff Friesen introduces the concepts of locks, synchronization, and the dangers of deadlock. Aug. 2, 2004

Java Tech: An Intelligent Nim Computer Game, Part 2
In the previous Java Tech, Jeff Friesen showed how to create the logic for a computerized game of Nim. This month, he wraps up by using this in two complete versions of the game, one for console I/O and one with a Swing GUI. Jun. 21, 2004

Java Tech: An Intelligent Nim Computer Game, Part 1
Offering a two-player game that only a single player can enjoy requires writing a computer opponent that's "smart" enough to be an interesting opponent. Java Tech columnist Jeff Friesen shows how to write a Java application to play the game of Nim. May. 18, 2004

Java Tech: Using Variable Arguments
J2SE 1.5 introduces the idea of variable arguments, or varargs, to method signatures. As Jeff Friesen explains in his first Java Tech installment, this makes many method calls more convenient and opens the door to a C-style printf().  Apr. 19, 2004