AppFuse1.8中BaseAction的一些主要方法说明

功能：

通过请求的参数来决定该执行哪一个方法，而不像一般的Action，从Execute方法执行。在一个窗体中包括两个以上同名的按钮时，由Struts来决定具体执行那个按钮操作，减少了Action类，增加了请求处理的灵活性

AppFuse1.7与AppFuse1.8的BaseAction区别

AppFuse1.7是继承LookupDispatchAction, 需要复写 getKeyMethodMap()方法

具体可参考http://blog.csdn.net/GOALSTAR/archive/2005/12/05/543802.aspx

AppFuse1.8是继承DispatchAction

AppFuse1.8中BaseAction的主要方法



1.getBean()方法,得到Bean的对象

public Object getBean (String name) {

     if (ctx == null) {

            ctx = WebApplicationContextUtils.getRequiredWebApplicationContext(servlet.getServletContext());

     }

      return ctx.getBean(name);

}



2.convert() 对象转换方法,用来实现POJOs à ActionForm & ActionForm à POJOs 的转换

// 调用ConvertUtil#convert(java.lang.Object)
protected Object convert (Object o) throws Exception {

              return ConvertUtil.convert(o);

}



3.execute()的方法

public ActionForward execute (ActionMapping mapping, ActionForm form,

                          HttpServletRequest request, HttpServletResponse response)

    throws Exception {

       

        if (isCancelled(request)) {

            try {

                getMethod("cancel");

                return dispatchMethod(mapping, form, request, response, "cancel");

            } catch (NoSuchMethodException n) {

                log.warn("No 'cancel' method found, returning null");

                return cancelled(mapping, form, request, response);

            }

        }



        // Check to see if methodName indicated by request parameter

        String actionMethod = getActionMethodWithMapping(request, mapping);

       

        if (actionMethod != null) {

            return dispatchMethod(mapping, form, request, response, actionMethod);

        } else {

            String[] rules = {"edit", "save", "search", "view"};

            for (int i = 0; i < rules.length; i++) {

                // apply the rules for automatically appending the method name

                if (request.getServletPath().indexOf(rules[i]) > -1) {

                    return dispatchMethod(mapping, form, request, response, rules[i]);

                }

            }

        }

       

        return super.execute(mapping, form, request, response);

    }


在AppFuse1.8中BaseAction是继承DispatchAction , 使用struts时我们经常会用到DispatchAction.有了这个类,我们不需要针对每一个Action都要写一个特定的类,而是可以把一些相关的方法放到一个类中.
DispatchActon中使用了reflection来根据你传入的method参数的值来获取相应的参数来处理你的请求.正如他的方法 -- 他根据你传入的请求参数,用不同的方法来处理你的请求.

   只要看看struts中DispatchAction(以下简写做DA)的源文件你就会发现,它有一个dispatchMethod方法,接受5个参数.其中4个就是我们通常的struts action里的(mapping,request,response,form),还有一个参数就是指定方法的参数的名字.



Ø Struts-config.xml中的配置

<action path="/editUser" ype="smarthings.webapp.action.UserAction"  name="userForm" scope="request"

input="list" roles="admin" parameter="method" unknown="false" validate="false" >

<forward name="viewUsers" path="/editUser.html?method=Search( edit / save / delete )"/>

</action>



然后在Action中具体的实现Action都是继承了BaseAction的.比如

  public final class PeopleAction extends BaseAction {

    //具体的操作方法search

    public ActionForward search(ActionMapping mapping, ActionForm form,

                                HttpServletRequest request,

                                HttpServletResponse response)

         throws Exception {

        //具体的操作方法cancel

    public ActionForward cancel(ActionMapping mapping, ActionForm form,

                                HttpServletRequest request,

                                HttpServletResponse response)

    throws Exception {………}

//具体的操作方法delete

    public ActionForward delete(ActionMapping mapping, ActionForm form,

                                HttpServletRequest request,

                                HttpServletResponse response)

         throws Exception {………}



//具体的操作方法Edit

   public ActionForward edit(ActionMapping mapping, ActionForm form,

                                HttpServletRequest request,

                                HttpServletResponse response)

         throws Exception {……}

………

………