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Preparing for an interview? Want to just revisit Java SE 7 features? Trying to recollect or revise a Java SE programming construct? Let me take you back in time to what was introduced first in Java SE 7? Join me for this tutorial series on Java as we all eagerly await the official release of Java SE 9. Java SE 7 Release Date: 28-07-2011 Java SE 7 Code Name: Dolphin Java SE 7 Highlights Strings in switch statements. Automatic resource management in try statements. Improved type inference for generic instance creation, AKA the diamond operator <>. Simplified varargs method declaration. Binary integer literals. Allowing underscores in numeric literals. Catching multiple exception types and rethrowing exceptions with improved type checking. I have provided some of the most important core language enhancements for JDK 7.0, along with code samples. The examples provided bel... (more)

Sun Launches JavaFX Mobile

Sun Microsystems announced the availability of the JavaFX Mobile platform, enabling the Java wireless ecosystem to create expressive solutions, which leverage the power and ubiquity of the Java Platform Micro Edition (Java ME). The JavaFX Mobile platform delivers rich content and services across a range of mobile devices - from mass market feature phones to smart phones. Sun also announced that several leading handset manufacturers, service providers and ISVs are working with Sun to ship JavaFX Mobile handsets. The Java platform is supported by global mobile operators and device manufacturers, is available on more than 2.6 billion mobile phones and is supported by 6.5 million software developers. Built on top of a consistent Java ME platform implementation, JavaFX Mobile allows companies to create immersive mobile content, while leveraging their existing investment i... (more)

Terracotta Claims To Solve Java’s Memory Conundrum

Java developers might want to think about hoisting Terracotta on their shoulders and marching around JavaOne this weekend. The company thinks it's overcome the garbage collection-created impasse preventing Java apps from using lots of memory just when lots of memory has gotten terribly fashionable in modern servers. And the solution is a lot cheaper and simpler than buying what amounts to a mainframe for Java from Azul. It'll be at JavaOne showing off the beta of its new BigMemory pure Java add-on for Enterprise Ehcache. The widgetry, compatible with all the popular JVMs, offers an off-heap cache that frees Java applications from the memory and performance restraints of garbage collection by managing the memory directly. See, JVMs and their attendant applications data are pretty much restricted to 2GB-4GB of in-memory cache, which explains why VMs have proliferate... (more)

An Introduction to Abbot

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)

Java for Managers -- What Should They Know?

Last month, JavaBlackBelt completed a survey where developers said their teams would be 25% more productive if their management committed to skills management... which led me to consider: Which Java technologies do developers think that managers should understand better in order to make great decisions about skills management? I'll suggest, as a start: -- Java SE and EE basics -- ORM's (Hibernate, ...) -- Web Frameworks (lStruts 2, ...) -- IDEs (Eclipse, ...) -- Source Code Mgmt -- Testing Methods -- JavaScript -- Ajax Very open to your thoughts, and who might find such a course useful... feel free to comment here and/or send email to java4managers@globalforcedirect.com. ... (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)

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)

JDJ Editorial: IT Olympics

There are a number of esteemed contests for the greatest and fastest software developers among us - events where we can pit our coding prowess against fellow brainiacs and like-minded techies. I think it's high time we had an alternative set of awards, suited not to aspiring budding Turing machine engineers, but rooted more in the humdrum real, rather than artificial academic, world. The Herring Rouge Chase To win this award you have to think that when a piece of code you authored isn't working correctly that the problem isn't your error but instead lies elsewhere in the broken software stack. A colleague of mine was once so convinced the JVM was broken he got as far as talking to a Sun engineer by phone, when it transpired eventually that he'd just written a bad toString() method. Everyone has had or witnessed one of these moments, for which we should humbly remin... (more)

A Framework for REST in Java

Not long ago I worked on a team charged with building up a Java-based REST infrastructure. Our goals were to first support what was then an emerging specification for Java-based RESTful services called JAX-RS. Beyond that, we had thoughts of building an entire framework, both server and client, around RESTful services written in Java. Some of the people I worked with on that team are now part of the team that is responsible for an open source implementation called Apache Wink which embodies some of our early ideas and much more. Developers have been implementing RESTful services in Java for a long, long time, so what's the deal with JAX-RS and an entire framework? Well, the way developers have been implementing REST services typically involves writing their own custom servlet. Within the servlet they write custom code to route incoming requests to the proper back-e... (more)