A more complex Struts application
In order to be able to develop a Struts application we need to go one step
further. This is evident if we, for example, import the
struts-validator war-file in a new Tomcat project. Several of the class
files will be flagged with errors:
These errors will disappear when we add the Struts jar-files to the classpath.
Right click the project, select Properties, Java Build Path, Libraries. Click
the "Add JARs..." button and add all the jar files from the lib
directory:
Press "OK" and the flags will disappear. Again, try the Validator
after having reloaded Tomcat, by using this address:
http://localhost:8080/StrutsValidation
On the page that is shown, you may try several of the Validator features
available in Struts.
Since this project is more "real-life" than the other ones we have
used in the article, you might want to see the debugging features in a more
realistic environment. Try for example to set a breakpoint in the
Action class
MultiRegistrationAction:
In the browser select the link "Multi-page Registration Form",
and fill in some values in the HTML form, and press Save. The Eclipse debugger
is now active, and the
Action class's variables may be inspected--and changed-- for example the
form fields:
If you change something in the
MultiRegistrationAction class and save it, you'll see Tomcat re-loading
several files, for example the Validator's XML-files. Not every changed file
will force a reload, however. If you change
struts- config, you'll have to reload it manually, as described above.
Conclusion
When considered separately Eclipse, Tomcat, and Struts are all great software
products. Used together their value is further increased to give you a very
solid development environment, with a lot of the features that you need and
should expect from development tools of today. If you further add a few other
tools like
Log4J (for
logging),
JUnit and
StrutsTestCase for unit
test, and also implement some solid error handling, you really have what's
needed to work productively.
But you'll have to try it out for yourself, and my advice is to use the time
needed to get to know the tools. Eclipse has a lot of very useful features, like
code-completion, refactoring and source formatting. Read the help files and try
the features out.
When we look at Struts, then its full potential only becomes apparent when you
work with it. My advice is to read articles on the web or buy one of the good
books on Struts. See the resources section for hints.
Happy coding!
Resources
Keld is currently working as a web
architect for one of the largest IT companies in Denmark. He battled with the
mainframes during the 70's when they were the size of a gymnasium and had the
power of your PalmPilot. He also struggled with CASE-tools in the 90s and now
explores the cutting edge technology of the Web. While not busy at his computer
he likes to vacation on the Greek islands.
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