Liferay默认提供的基于
Struts Action扩展的PortletAction是不支持多分发命令的，也就是我们一般常用的DispatchAction。
但在我们日常基于
Struts处理的操作中，已经大量的沿用了DispatchAction处理方式，采用“cmd=queryall”诸如此类的方式。
<
portlet-class
>
com.liferay.portlet.StrutsPortlet
</
portlet-class
>
<
init-param
>
<
name
>
view-action
</
name
>
<
value
>
/ext/reports/view_reports
</
value
>
</
init-param
>
本文就来给大家讲解如何通过扩展，让
Liferay实现对多分发命令Action的支持。
首先让我们来看看
Liferay是如何处理的：
在
portlet.xml中，我们一般会配置如下：
<
portlet-class
>
com.liferay.portlet.StrutsPortlet
</
portlet-class
>
<
init-param
>
<
name
>
view-action
</
name
>
<
value
>
/ext/reports/view_reports
</
value
>
</
init-param
>
这样
Liferay面对一个Portlet请求的时候，会根据请求model来执行Portlet的doView或doEdit方式。当执行doView的时候就会请求其view-action所配置的Action URL所代表的Action来处理。
其处理流程大致是：
Portlet类——〉RequestProcessor——〉StrutsAction处理类
。
我们可以通过两种扩展方案来实现对多分发的支持：
方案（一）：
扩展
Liferay的StrutsPortlet类，并写一个DispatchPortletAction类，这样不用扩展RequestProcessor实现。
方案（二）：
扩展
RequestProcessor 与，并写一个DispatchPortletAction类，这样可以直接使用Liferay所提供的StrutsPortlet类。对于 RequestProcessor的扩展，在通过portal.properties文件中通过配置 “struts.portlet.request.processor”属性来设置。
接下来就两种方案做分别的详细讲解（本篇先讲方案一）：
方案（一）
首先让我们写一个
DispatchPortletAction 类，此类可以通过扩展Liferay本身的PortletAction实现，也可以通过扩展Struts本身的DispatchAction实现。本人是选择后一种方式，这样扩展的代码量较少，都不要自己写execute方式，直接使用基类的即可。
对于
DispatchPortletAction 主要扩展dispatchMethod和getMethodName方法。注意在getMechodName方法中，还追加了从 request.getAttribute(parameter)获取方法名称，并注意unspecified方法，这个是在没有指明访问方法的时候默认执行的，所以开发人员在后续写自己的Action一定要实现这个。
public
class
DispatchPortletAction
extends
DispatchAction
{
protected
ActionForward dispatchMethod(ActionMapping mapping,
ActionForm form, HttpServletRequest request,
HttpServletResponse response, String name)
throws
Exception
{
PortletConfig portletConfig
=
(PortletConfig) request
.getAttribute(WebKeys.JAVAX_PORTLET_CONFIG);
RenderRequest renderRequest
=
(RenderRequest) request
.getAttribute(WebKeys.JAVAX_PORTLET_REQUEST);
RenderResponse renderResponse
=
(RenderResponse) request
.getAttribute(WebKeys.JAVAX_PORTLET_RESPONSE);
if
(name
==
null
)
{
return
this
.unspecified(mapping, form, portletConfig,
renderRequest, renderResponse);
}
Method method
=
null
;
try
{
method
=
getMethod(name);
}
catch
(NoSuchMethodException e)
{
String message
=
messages.getMessage(
"
dispatch.method
"
,
mapping.getPath(), name);
log.error(message, e);
String userMsg
=
messages.getMessage(
"
dispatch.method.user
"
,
mapping.getPath());
throw
new
NoSuchMethodException(userMsg);
}
ActionForward forward
=
null
;
try
{
Object args[]
=
{ mapping, form, portletConfig, renderRequest,
renderResponse }
;
forward
=
(ActionForward) method.invoke(
this
, args);
}
catch
(ClassCastException e)
{
String message
=
messages.getMessage(
"
dispatch.return
"
,
mapping.getPath(), name);
log.error(message, e);
throw
e;
}
catch
(IllegalAccessException e)
{
String message
=
messages.getMessage(
"
dispatch.error
"
,
mapping.getPath(), name);
log.error(message, e);
throw
e;
}
catch
(InvocationTargetException e)
{
Throwable t
=
e.getTargetException();
if
(t
instanceof
Exception)
{
throw
((Exception) t);
}
else
{
String message
=
messages.getMessage(
"
dispatch.error
"
,
mapping.getPath(), name);
log.error(message, e);
throw
new
ServletException(t);
}
}
return
(forward);
}
protected
String getMethodName(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response,
String parameter)
throws
Exception
{
String methodName
=
request.getParameter(parameter);
if
(methodName
==
null
||
methodName.length()
==
0
)
{
methodName
=
(String) request.getAttribute(parameter);
}
return
public
class
DispatchPortletAction
extends
DispatchAction
{
protected
ActionForward dispatchMethod(ActionMapping mapping,
ActionForm form, HttpServletRequest request,
HttpServletResponse response, String name)
throws
Exception
{
PortletConfig portletConfig
=
(PortletConfig) request
.getAttribute(WebKeys.JAVAX_PORTLET_CONFIG);
RenderRequest renderRequest
=
(RenderRequest) request
.getAttribute(WebKeys.JAVAX_PORTLET_REQUEST);
RenderResponse renderResponse
=
(RenderResponse) request
.getAttribute(WebKeys.JAVAX_PORTLET_RESPONSE);
if
(name
==
null
)
{
return
this
.unspecified(mapping, form, portletConfig,
renderRequest, renderResponse);
}
Method method
=
null
;
try
{
method
=
getMethod(name);
}
catch
(NoSuchMethodException e)
{
String message
=
messages.getMessage(
"
dispatch.method
"
,
mapping.getPath(), name);
log.error(message, e);
String userMsg
=
messages.getMessage(
"
dispatch.method.user
"
,
mapping.getPath());
throw
new
NoSuchMethodException(userMsg);
}
ActionForward forward
=
null
;
try
{
Object args[]
=
{ mapping, form, portletConfig, renderRequest,
renderResponse }
;
forward
=
(ActionForward) method.invoke(
this
, args);
}
catch
(ClassCastException e)
{
String message
=
messages.getMessage(
"
dispatch.return
"
,
mapping.getPath(), name);
log.error(message, e);
throw
e;
}
catch
(IllegalAccessException e)
{
String message
=
messages.getMessage(
"
dispatch.error
"
,
mapping.getPath(), name);
log.error(message, e);
throw
e;
}
catch
(InvocationTargetException e)
{
Throwable t
=
e.getTargetException();
if
(t
instanceof
Exception)
{
throw
((Exception) t);
}
else
{
String message
=
messages.getMessage(
"
dispatch.error
"
,
mapping.getPath(), name);
log.error(message, e);
throw
new
ServletException(t);
}
}
return
(forward);
}
protected
String getMethodName(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response,
String parameter)
throws
Exception
{
String methodName
=
request.getParameter(parameter);
if
(methodName
==
null
||
methodName.length()
==
0
)
{
methodName
=
(String) request.getAttribute(parameter);
}
return
