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Graphical user interface (GUI) testing is a potentially problematic area because constructing effective test cases is more difficult than the corresponding application logic. The roadblocks to effective functional GUI testing are: Traditional test coverage criteria like "80% coverage of the lines of code" may not be sufficient to trap all the user interaction scenarios. End users often use a different user task interaction model than the one conceived by the development team. Functional GUI testing needs to deal with GUI events as well as the effects of the underlying application logic that results in changes to the data and presentation. The common methods for functional GUI testing are the "record and execute" script technique and writing test programs for different scenarios. In the "record and execute," the test designer interacts with the GUI and all the eve... (more)

How to Diagnose Java Resource Starvation

We can visualize resource starvation using an elaborate rendition of the Dining Philosophers Problem. This classic metaphor of resource allocation among processes was first introduced in 1971 by Edsger Dijkstra in his paper "Hierarchical Ordering of Sequential Processes." It's been a model and universal method for verifying theories on resource allocation ever since. The metaphor goes like this: There are three well-known philosophers in an Asian bistro. Dinner is served but they are only given three chopsticks because the restaurant's supply truck has been stuck in a snow storm for a couple of days. Naturally each philosopher needs two chopsticks to eat his dinner and each is protected from interference while he uses a chopstick. Plato skipped lunch that day and insists that he should have priority or else he'll faint. If he doesn't give up his chopsticks, the other ... (more)

eLearning + Coaching = Breakthrough in Java Skills?

JavaBlackBelt just announced its “Coached e‐Learning” for Java developers. In a developer survey to be released next week, this Coached e‐Learning was selected as the #1 choice for Java learning compared with classroom training and self‐paced e‐Learning. Here’s how it works: 1. In these courses, the coach meets with the student to begin each course, reviews the course plan and materials, and agrees to a schedule. 2. The student then learns at their own pace from the JavaBlackBelt eLearning platform ‐‐ online materials and videos, community forums, exercises, and exams. 3. Along the way, the coach checks intermediate goals, answers questions, helps overcome obstacles, and oversees progress. 4. The course is completed when the student passes the final exam, which, depending on the student’s schedule and pace of learning, follows one to two weeks of coursework. The ... (more)

Java Kicks Ruby on Rails in the Butt

This article tries to demonstrate that Java can be more productive than Ruby. We are going to develop the same application of the article Rolling with Ruby on Rails Revisited (part 1 [1] and part 2 [2]) but using POJO [3]s annotated with JPA [4] and a Model Driven Framework, OpenXava [5] in this case. The result is that with less code, and less time you obtain a more powerful application. Ruby and rails: The regressive framework Ruby on rails [6] is so elegant, so easy, so productive. I cannot avoid read and heard continuously these comments. For example, the article Rolling with Ruby on Rails Revisited of Bill Walton says: “What would you think if I told you that you can develop a web application at least ten times faster with Rails than you can with a typical Java framework?” Oops! Ten times faster! Well, after these comments I decided to learn Ruby on Rails. I ne... (more)

Insane Strings

Java Developer's Journal A cool article at http://www.roseindia.net/javatutorials/insane_strings.shtml You never know what can happen with Java code . ... (more)

Reflections on Java Command Line Options

Abstract There are many different types of command line options that programs need to recognize. Many languages (e.g.: bash and perl) has built-in processing of command line options; Java does not. The Java Command Line Options (JCLO) package performs this task for a variety of option styles. It also uses Java's reflection capability to automatically assign values to variables in a specified class. Introduction Even in these days of sophisticated graphical user interfaces, many programs have a wide variety of command line options that help specify their behavior. It is also the case that command line only programs continue to enjoy wide use. It is also the case the command line arguments can become quite complicated, e.g.: -Djava.util.logging.config.file=All.finest -1 --list --this=that Some languages have built-in parsers for command line options; perl and bash ar... (more)

Why Cops and Java Developers Have Low Salaries?

I've read an interesting article by Felipe Gaucho called "Good Java Developers Deserve Better Salaries," where he states that employers have to increase salaries for Java developers. Unfortunately, in the market economies such demands won't work. In enterprise IT no one just raises salary if there is a way to hire someone else for less money. It's just not in the corporate culture where people are treated as nameless resources. Have you ever wondered why policemen get lower salaries than Java developers even though people in the uniform risk their lives on daily basis?  It's because there are many people who apply for jobs in the police. Preparing a mediocre policemen takes about the same time as preparing a mediocre Java programmer. The same holds true for good policemen and Java developers. Market rules.  If no one will want to go to police, their salaries and per... (more)

Agile Testing Solution for Java

Traditional testing methods are long, drawn out and tedious. Moreoften than not organizations spend millions of dollars testing their scripts using a technique that can be slow, costly and sometimes incorrect. ETM is my attempt to address this lag, a bottleneck in your IT assembly line, that can bring your whole project to a grinding halt. Traditional, testing approaches require four major entities to work with each other. These are: The Tester The Developer The Business Owner The Business User The Developer develops the software based on some requirements from the Business Owner. Once the software has been developed, the developer does some Unit Testing. Satisfied with the results of his Unit Testing, the developer pushes the application to the next stage, where it will go through a series of tests to ensure its quality and compliance. Enter the Tester, the protagon... (more)

WebRenderer Swing Edition 6 Released

JadeLiquid is pleased to announce the long-awaited release of the WebRenderer Swing Edition 6.0 supporting 64-bit systems. WebRenderer 6.0 includes support for both 32 and 64-bit systems on Windows, OS X and Linux. SPARC Solaris is also a supported platform. The WebRenderer Swing Edition 6.0 release is the most advanced version of WebRenderer ever released. WebRenderer Swing Edition renders in lightweight Swing and is the only commercial strength Java browser SDK with this capability. New features found in the WebRenderer 6.0 include an updated Firefox engine, HTML5, SVG, Canvas, MathML and vastly improved font rendering. WebRenderer Swing Edition 6.0 also features much improved overall performance in the areas of JavaScript and rendering speed. The standard full-featured WebRenderer API is implemented and the W3C DOM and plugins such as Flash and PDFs are supported.... (more)

Anatomy of a Java Finalizer

A couple of patterns that could cause Java heap exhaustion were identified from years of research at IBM. One interesting scenario was observed when Java applications generated an excessive amount of finalizable objects whose classes had non-trivial Java finalizers. What Is a Java Finalizer? A Java finalizer performs finalization tasks for an object. It's the opposite of a Java constructor, which creates and initializes an instance of a Java class. A Java finalizer can be used to perform postmortem cleanup tasks on an instance of a class or to release system resources such as file descriptors or network socket connections when an object is no longer needed and those resources have to be released for other objects. You don't need any argument or any return value for a finalizer. Unfortunately the current Java language specification does not define any finalizers for a... (more)

Interviewing Java Developers With Tears in My Eyes

During the last week I had to interview five developers for a position that required the following skills: Flex, Java, Spring, and Hibernate.  Most of these guys had demonstrated the 3 out of 10 level of Flex skills even though each of them claimed a practical experience on at least two projects. But this didn’t surprise me – Flex is still pretty new and there is only a small number of developers on the market who can really get Flex things done. What surprised me the most is a low level of Java skills of most of these people. They have 5-8 years of Java EE projects behind their belts, but they were not Java developers. They were species that I can call Robot-Configurator.  Each of them knew how to configure XML files for Spring, they knew how to hook up Spring and Hibernate and how to map a Java class to a database entity. Some of them even knew how to configure laz... (more)