Purpose of having '.do'

[avaj eikunj]

What is the purpose of having '.do' in the actions or URL? why .do? Why not just leave it as it is? such as '/browse' instead of /browse.do ?

[debraj mallick]

if you are not happy with .do change it, like

    <servlet-mapping>
        <servlet-name>action</servlet-name>
        <url-pattern>*.avaj</url-pattern>
    </servlet-mapping>

also you can try URL rewrite
http://www.tuckey.org/urlrewrite/
http://urlrewritefilter.googlecode.com/svn/trunk/src/doc/manual/3.2/index.html

[avaj eikunj]

No no.....what I meant was why one should even have a .do or a .avaj? Wht cant it be

<servlet-mapping>
<servlet-name>action</servlet-name>
<url-pattern>/browseCatalog instead of /browseCatalog.do</url-pattern>
</servlet-mapping>

is it some kinda namespace we are trying to resolve to?

[Joe Ess]

The problem with a URL pattern of /browseCatalog is that you would only be able to map a single web context to a Struts action. You want to have some sort of wildcard so you can map multiple contexts and use multiple Struts actions.

[Kaur Manpreet]

Hi Joe,

Understand that if we specify an exact name in the <url-pattern> tag, we are mapping only one web context to a struts action and when we add *.do in the <url-pattern>, all URL's that have .do as extension would rightfully be mapped to struts action.

What I am unable to understand here is how is .do suffix appended to each and every URL. Is there a rule for that or is there some mapping which I overlook?

Thanks
Manpreet

[Bear Bibeault]

You can also use prefix mapping such as: /action/*

In fact, the move to "friendly" and RESTful URLs make the .do convention (which I have always detested) a bit antiquated.

[Kaur Manpreet]

Hi Bear,
My question is regarding the appending of extension .do (or any other specified in <url-pattern>) to the existing URL.

How is this happening?
Is it behind the scenes (as a rule or out of box feature of Struts).

Thanks

[Sandip Ram]

Hi,
Nice Question dear.
Before i mention the answer of your question first i want to tell the definition of of frame work.
"A framework defines a well defined procedure to carryout a task"
So the task means some work. And carry out means to do the work.
So struts guys are followed this convention and for doing the work they use do.
I think you clear a little bit.

This is for struts 1.x and for struts 2.x also now you guess what the do(just use action incase of .do ).

Thank you.

[Daniel Val]

Kaur Manpreet wrote:Hi Bear,
My question is regarding the appending of extension .do (or any other specified in <url-pattern>) to the existing URL.

How is this happening?
Is it behind the scenes (as a rule or out of box feature of Struts).

Thanks

Hi,

Struts is an MVC. Like any MVC, it has a front controller, which is the ActionServlet. All the requests within the application must go through the front controller who will then dispatch them to the right action.

The Action Servlet is defined with the url pattern *.do, that's why you see the calls like response.do etc.

How it is done: when you put <html:form /> tag, it will render a html form tag that will have action geared to the *.do url.

If you don't like *.do you can change it, however all the html form tags in your application will be rendered to direct all your posts to that ActionServlet front controller.

D.