Struts2 Study Code Tips in 2009

@Author: cjcj  [e-mail] <c-j.iteye.com>

一、体系结构：
     S1:
          
没找到合适的S1体系结构图。

    S2:
      



二、Comparing Struts 1 and 2

         S1                              
Struts 1 requires Action classes to extend an abstract base class.
Struts 1 Actions are singletons and must be thread-safe.
Struts 1 Actions have dependencies on the HttpServletRequest and HttpServletResponse is passed to the execute method when an Action is invoked.
Struts 1 Actions can not be tested.
Struts 1 uses an ActionForm object to capture input.
Struts 1 all the Actions in the module must share the same lifecycle.


          S2
An Struts 2 Action may implement an Action interface.
Struts 2 Action objects are instantiated for each request, so there are no thread-safety issues.
Struts 2 Actions are not coupled to a container. Most often the servlet contexts are represented as simple Maps, allowing Actions to be tested in isolation.
Struts 2 Actions can be tested.
Struts 2 uses Action properties as input properties.
Struts 2 supports creating different lifecycles on a per Action

三、Source Arch
 


org.apache.struts2.dispatcher 核心包，最重要的类都放在该包中。
org.apache.struts2.util 实用包。