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Seven Common Mistakes You Should Avoid When Handling Java Exceptions By Thorben Janssen Handling an exception is one of the most common but not necessarily one of the easiest tasks. It is still one of the frequently discussed topics in experienced teams, and there are several best practices and common mistakes you should be aware of. Here are a few things you should avoid when handling exceptions in your application. Mistake 1: Specify a java.lang.Exception or java.lang.Throwable As I explained in one of my previous posts, you either need to specify or handle a checked exception. But checked exceptions are not the only ones you can specify. You can use any subclass of java.lang.Throwable in a throws clause. So, instead of specifying the two different exceptions that are thrown by the following code snippet, you could just use the java.lang.Exception in the throws cla... (more)

X-oops, I did it again

(LinuxWorld) — One of my non-profit Web sites, VarLinux.org, ran on my modified version of the PHP-Nuke weblog package from the site's inception in March 2001 until late November 2002. I chose PHP-Nuke as a starting point because I was very impressed with it. However, the more I learned how to use PHP, the more I realized that PHP-Nuke was not only a tangled mess but that I had made it even worse with my modifications. A year later, I was faced with the fact that VarLinux.org was not only lame because it was based on PHP-Nuke, it was also showing its age. It lacked features of other weblogs, and still lacked many of the features I had intended to add to the site. If I were going to fix the code, the first thing I would do would be to make it an object-oriented system. I toyed with the idea of converting my code into OOP-based code, but I concluded that if the P... (more)

The i-Technology Right Stuff

Related Links: Wanted: 19 More of the Top Software People in the World Sung and Unsung i-Technology Heroes Who's Missing from SYS-CON's i-Technology Top Twenty?" Our search for the Twenty Top Software People in the World is nearing completion. In the SYS-CON tradition of empowering readers, we are leaving the final "cut" to you, so here are the top 40 nominations in alphabetical order. Our aim this time round is to whittle this 40 down to our final twenty, not (yet) to arrange those twenty in any order of preference. All you need to do to vote is to go to the Further Details page of any nominee you'd like to see end up in the top half of the poll when we close voting on Christmas Eve, December 24, and cast your vote or votes. To access the Further Details of each nominee just click on their name. Happy voting!   In alphabetical order the nominees are:   Tim Berner... (more)

Revisiting Java SE 7 Features | @CloudExpo #Java #Cloud #OpenSource

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)

i-Technology's All-Time Top 100?

Gene Amdahl: Implementer in the 60s of a milestone in computer technology: the concept of compatibility between systems Marc Andreessen: Pioneer of Mosaic, the first browser to navigate the WWW; co-founder of Netscape John Vincent Atanasoff: Inventor of an electronic computer in the late 1930s not for fun or glory, but because he had problems for it to solve Charles Babbage: Lucasian Professor of Mathematics at Cambridge in 1828; inventor of the 'calculating machine' John Backus: Inventor (with IBM) of FORTRAN (FORmula TRANslator) in 1956 Ralph Baer: "The man who invented video games" (Pong) Kent Beck: Creator of JUnit and pioneer of eXtreme Programming (XP) Bob Bemer: One of the developers of COBOL and the ASCII naming standard for IBM (1960s) Tim Berners-Lee: "Father of the World Wide Web" and expectant father of the Semantic Web D J Bernstein: Author of qmail Jos... (more)

Java Heap Space vs. Stack Memory | @CloudExpo #JVM #JRE #Java #AI #DX

Java Heap Space vs. Stack Memory: How Java Applications Allocate Memory By Angela Stringfellow Java applications need a certain amount of RAM on a computer to run. Each time an object or variable is declared, it needs more RAM. Simply designating enough memory to hold every value declared and run each method would lead to a bloated application. To keep application memory requirements lean, it is partitioned in ways that require less memory and allows the application to run more quickly. The Java Virtual Machine (JVM) divides memory between Java Heap Space and Java Stack Memory in a way that only uses memory that's needed. What Is Java Heap Space It is created by the Java Virtual Machine when it starts. The memory is used as long as the application is running. Java runtime uses it to allocate memory to objects and Java Runtime Environment (JRE) classes. When an object i... (more)

Who Are The All-Time Heroes of i-Technology?

I wonder how many people, as I did, found themselves thrown into confusion by the death last week of Jean Ichbiah (pictured), inventor of Ada.  Learning that the inventor of a computer programming language is already old enough to have lived 66 years (Ichbiah was 66 when he succumbed to brain cancer) is a little like learning that your 11-year-old daughter has grown up and left home or that the first car you ever bought no longer is legal because it runs on gasoline in an age where all automobiles must run on water. How can something as novel, as new, as a computing language possibly already be so old-fangled that an early practitioner like Ichbiah can already no longer be with us? The thought was so disquieting that it took me immediately back to the last time I wrote about Ichbiah, and indeed about Ada Lovelace for whom his language was named. It was in the context ... (more)

JDJ Archives: Eclipse vs NetBeans - "Point/Counterpoint" Special

This article was originally published in print on December 3, 2003"Eclipse represents the worst of Java" Lately, there's been a lot of guff spouted about how Sun isn't joining Eclipse. While I understand the bitterness aimed at Sun somewhat, I think that this particular brand of talk is counterproductive and, dare I say it, wrong. The talk tends to center around the concept of NetBeans and Eclipse using common technology, and I think this is misguided, and here's why. I really dislike Netbeans. I think it blows goats from here to Sussex, and considering that I live in the middle of the US, that's a lot of goats. Given the choice between NetBeans and... Notepad, I usually spend a minute pondering whether I can keep remembering to check extensions on filenames before realizing that I can, and I end up with sucky ol' Notepad instead of bothering with NetBeans. That sai... (more)

Secrets Of The Masters: Core Java Job Interview Questions

JDJ's Enterprise Editor, Yakov Fain (pictured) writes: If you are planning to hit the job market,  you may need to refresh some of the Java basic terms and techniques to prepare yourself for a technical interview. Let me offer you some of the core Java questions that you might expect during the interviews.  For  most questions  I’ve provided only  short  answers to encourage further research.  I have included only  questions for mid (*) and senior level (**) Java developers. These sample questions could also become handy for people who need to interview Java developers (see also the article "Interviewing Enterprise Java Developers"). Disclaimer. This article has been originally published three or four years ago, hundreds of thousands Java developers have read it, but I still use some of these questions while interviewing Java developers. Guess what? Every other Jav... (more)

WebSphere First Look: Introducing IBM Workplace Designer 2.5

This article will introduce you to Workplace Designer 2.5. We begin with a brief overview of Workplace Designer and how you can use it to create Workplace applications. We then take a closer look at some of the many features included in Workplace Designer. We assume that you have experience with Web application development. Some familiarity with IBM Workplace products (such as IBM Workplace Collaboration Services 2.5 and IBM Workplace Services Express 2.5) would also be helpful. What is Workplace Designer? If your background is in Notes/Domino programming, you can think of Workplace Designer as a tool for providing Domino Designer-type application development functionality to the IBM Workplace family of products. In fact, those familiar with Domino Designer will notice a lot of similarities with many IBM Workplace Designer features and concepts described later in thi... (more)

Rich Internet Applications - State of the Union

[This prescient article first appeared on SYS-CON.com nearly 12 months ago.] We are entering an era of Rich Internet Applications (RIA),  and many enterprise development managers are facing the dilemma - which way to go - remain with  tried and true Java or .Net technologies or less known yet AJAX, Flex, OpenLaszlo or a number of other vendors.  This article is an attempt to give a brief overview of what's out there on the RIA market. Historically there have been major shifts in the software industry. We moved from mainframes with dumb terminals to client/server. Users gained in convenience and productivity, and mainframe systems were patronizingly labeled as legacy. With the availability of the World Wide Web industry visionaries turned the tables: vendors and corporate IT had been eager to get rid of the complexity of client/server version management and technologist... (more)