Atif Khan’s Blog

As the Web 2.0 grows in popularity, so does the urge for a lot of organizations to revamp their legacy applications and make them web based. Their are obvious benefits to this as the application becomes more accessible and requires less effort to deploy and maintain as there is single point of deployment and maintenance, the application server. What gets lost in all this excitement is the functionality that may have been available in the existing applications with rich user interfaces can not be easily replicated in the web application replicating it. By using the readily available javascript libraries and AJAX techniques some of this pain can be alleviated. It’s not necessary that web applications may always lose the usability of functionality of the original application. In fact they can actually simplify some of the transactions if the user experience is considered from beginning during the rewrite process.

It has a rich set of components and event model that can all be used and programmed to using the LZX language. You can also write your own components using the LZX markup. The important thing to keep in mind is that OpenLaszlo is strictly a UI technology. You still need to get your data to display from the backend whether it being database of another middleware. This is where OpenLaszo excels. At the core it can interact with a back end system using the RPC. Various RPC options include:

• Java RPC
• SOAP
• XML RPC
• XMLHttpRequest for Ajax

So, you can pretty much have you back end written in Java, PHP, Ruby or whatever you like as long as it supports either RPC, SOAP or XMLHttpRequest. If you are wondering about what do you need on your server to run OpenLaszlo, it is basically a Java Servlet based web application. So, you do need the Java servlet container on your server to run OpenLaszlo. That shouldn’t be an issue at all if you already use Java.

If you do use Java on the server side and you have been trying to decide between various web application frameworks available and there are a ton of them :), OpenLaszlo can make your life a little simpler as you don’t have to worry about the components or the component state management (JSF, Wicket, Tapestry etc). All you need is a solid framework that can preferably produce XML output and serve some data (Struts, WebWork, Spring MVC, RIFE) or any other similar framework and leave the UI aspect to OpenLaszlo. OpenLaszlo may not be suitable in all the cases, but it is worth a look if you want a web application with the look and feel and usability of a desktop application.