]]>Tomcat Architecture Diagramhttp://www.aygfsteel.com/honzeland/archive/2010/05/10/320458.htmlhonzelandhonzelandMon, 10 May 2010 02:39:00 GMThttp://www.aygfsteel.com/honzeland/archive/2010/05/10/320458.htmlhttp://www.aygfsteel.com/honzeland/comments/320458.htmlhttp://www.aygfsteel.com/honzeland/archive/2010/05/10/320458.html#Feedback0http://www.aygfsteel.com/honzeland/comments/commentRss/320458.htmlhttp://www.aygfsteel.com/honzeland/services/trackbacks/320458.html
Valve and Filter:
"Valve" is Tomcat specific notion, and they get applied at a higher level than anything in a specific webapp. Also, they work only in Tomcat.
"Filter" is a Servlet Specification notion and should work in any compliant servlet container. They get applied at a lower level than all of Tomcat's
Valves.
However, consider also the division between your application and the application
server. Think whether the feature you're planning is part of your application, or is it rather a generic feature of the application server, which could have uses in other applications as well. This would be the correct criteria to decide between Valve and Filter.
Order for filter: The order in which they are
defined matters. The container will execute the filters in the order
in which they are defined.
]]>Web application design: the REST of the storyhttp://www.aygfsteel.com/honzeland/archive/2010/01/08/308718.htmlhonzelandhonzelandFri, 08 Jan 2010 06:50:00 GMThttp://www.aygfsteel.com/honzeland/archive/2010/01/08/308718.htmlhttp://www.aygfsteel.com/honzeland/comments/308718.htmlhttp://www.aygfsteel.com/honzeland/archive/2010/01/08/308718.html#Feedback0http://www.aygfsteel.com/honzeland/comments/commentRss/308718.htmlhttp://www.aygfsteel.com/honzeland/services/trackbacks/308718.htmlWeb application design: the REST of the story
Key points:
HTTP is a very general, scalable protocol. While most people only
think of HTTP as including the GET and POST methods used by typical
interactive browsers, HTTP actually defines several other methods that
can be used to manipulate resources in a properly designed application
(PUT and DELETE, for instance). The HTTP methods provide the verbs in a web interaction.
Servers are completely stateless. Everything necessary to service a request is included by the client in the request.
All application resources are described by unique URIs. Performing
a GET on a given URI returns a representation of that resource's state
(typically an HTML page, but possibly something else like XML). The
state of a resource is changed by performing a POST or PUT to the
resource URI. Thus, URIs name the nouns in a web interaction.
