For the past couple of months I've been working on porting a PHP application to Java EE using JSF, JPA and EJB 3 (in case you are wondering, yes, I've been using NetBeans and GlassFish).
I've never had any real exposure to PHP, so this is a new experience for me. I'm not sure if what I'm seeing is typical PHP code, but comparing this legacy system to the typical enterprise Java system shows some striking differences in architecture. When analyzing the PHP code, it became obvious to me that the mindset of PHP developers is very different from your typical Java developer.
In the Java world, we love our design patterns, we can't live without our DAO's and MVC. In PHP, it seems to be no big deal to mix presentation, business logic and data access in a single file.
Having worked with Java for over 13 years and Java EE/J2EE for about 10 years, I have to confess that the architecture (if you can call it that, more like "lack of architecture") seemed appalling to me. In the enterprise Java world, we've been conditioned to think that separation of concerns is a good thing.
Our presentation logic should contain presentation only, that way if in the future we want to switch say, from straight JSPs and servlets to JSF, the rest of the code shouldn't be affected. Additionally, if we want to convert our web application to a desktop application using Swing, it should be fairly straightforward to do so.
Data access logic should be done via Data Access Objects (DAO's), that way if today we are using straight JDBC and tomorrow we want to use an object relational mapping tool such as JPA or Hibernate, all we need to do is change the data access layer, the rest of the code should not be affected.
Communication between layers in our applications should be done via Value Objects, which shouldn't really change if we change our data access layer or presentation layer.
Controllers should manage flow from one page to another, again these should only be rewritten if we change our presentation layer. Most Java web application frameworks provide their own controllers, however they are not self sufficient, for example, in Struts we need to use Actions and in JSF we need to write managed beans, therefore changing the presentation layer would usually involve changing the controller as well.
After analyzing the code for the legacy system I got the impression that PHP is a language for amateurs and Java/J2EE/Java EE is for professional software engineers and architects. Am I right? Or I am just a Java snob? Feel free to set me straight.
