Technology

Log statements help record the flow of an application’s execution. Hence they are an important part of software coding process. For the Java language the common Log API libraries are Java Util Logger (commonly known as JUL), Apache Log4J, SLF4J etc. While these libraries support many advanced capabilities, most developers only use a handful of features. For example, ability to send log messages to files and the ability change log levels dynamically etc.

In this blog I will compare JUL against SLF4J and focus on these above mentioned features. Many will argue that this is not a fair comparison since SFL4J is really a facade and supports JUL as well. To clarify, I will compare the SimpleLogger that is bundled with SLF4J against direct JUL usage.

In my first YouTube video, I discuss 3 networking concepts:

• Default Gateway
• DNS Server
• Subnet Mask

HTML5 Local Storage is a browser based key-value database that is available for client side applications. Java programmers (like me) will find that  HTML5 Local Storage is very similar to HashMap (or Hashtable). It is important to remember that Local Storage is available to client side applications even across browser restarts. In that context, Local Storage is similar to cookies. **But unlike cookies, Local Storage is not accessible to the server side applications. **Also cookies provide very limited storage (4 KB).

The release 2 (R2) of my URL Generator Project is now ready. You can check it out at the usual location. I am happy to share that this revision was completed on time as per my revised project plan. Of course the announcement was delayed a bit. The main additions to this version of the URL generator are HTML5 based Local Storage, a simple usage of Object-oriented JavaScript techniques and jQuery.

In the previous post we looked at the fundamental building blocks of physical and virtual networks. Now let us look at two key concepts in physical and virtual networks. They are Ports and VLAN.

In order understand Virtual Networking let us start with the simplest network that many of us operate every day – our home network. The picture below captures what a typical home network looks like. I am sure most of us use wireless rather than wired networks at home but the underlying concepts are very much alike.

Upcoming technologies like OpenFlow and SDN are altering the networking landscape very quickly. The underlying drivers are Cloud Computing and Virtualization. Servers, Storage and Networking make up the trinity for effective Cloud computing strategy. Servers and Storage Virtualization has helped drive the adoption of flexible cloud services already. Now it is time for Network Virtualization.

At the beginning of the year, Scott Lowe, a specialist in virtualization, networking and storage, posted his project list for 2012. He had set a few goals for his learning and development. Last week [Scott posted an honest assessment][1] of how he has been performing on his own goals.

Why would anyone share their personal goals on the Internet? Because once you share your goals, visitors of your blog and people who know you would like to know how you are progressing. This curiosity will result in a sense of accountability and push you to ensure systematic progress on those goals. Another benefit is that you will plan your goals and the deliverables better.

If you write networking or IO oriented programs using Java, there will be several situations where the code on the server will catch multiple exceptions. Most of the times the exceptions are logged, sometimes they are logged and re-thrown.