The main function of a good logging implementation is to provide a clear overview of the functioning of a system. Basically, the logging must describe the inner workings of a system and provide the necessary details to the readers of the log. In fact, good logging can drastically reduce maintenance costs of your applications, especially for clustered systems.

Logging is a crucial part of every system and provides all the information about the state of a system. The key is to provide this information without cluttering the code too much with these logging statements.

Most programmers tend to use a decent logging mechanism in their applications, but few of them use it elegantly. How can we make sure that we don’t clutter our code with unnecessary statements that reduce readability?

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From time to time I need some kind of mechanism to continuously refresh a web page in order to provide a real-time dashboard of some kind. It would be great if I only could refresh a part of a specific page, for example: the traffic lights on a dashboard that indicate the status of the system.

It is really easy to only refresh a part of the page by using the JQuery JavaScript library. Once we’ve included the JQuery library into our page, we only need 1 line of JavaScript to get it working:

<script src="/js/jquery-1.3.2.min.js" type="text/javascript"></script>

So we just place this little JS code snippet into our page to refresh everything inside the tag with the content id, let’s say every 5 seconds:

setInterval(function() {
    $("#content").load(location.href+" #content>*","");
}, 5000);

That’s it!! It is thus fairly easy to accomplish some real-time monitoring behavior with just that line of code. No more weird meta-refresh tags or iframe kind of workarounds in your web applications.

Every 5 seconds, we will refresh the content of the element with the content of the same URL and all elements that reside under the element with id: content.

Quite nice, don’t you think? JQuery certainly allows you to apply some very powerful techniques in just a few lines of code. I like it.. a lot!