本文转载自：http://www.cnblogs.com/jifeng/archive/2010/08/28/1810706.html
在此感谢作者的友情分享，首次备用。
解决办法:
在Struts2过滤器前增加一个过滤器，使用过滤器转发到servlet上
web.xml配置:
view sourceprint?01 <filter>
02 <filter-name>JSONRPCServlet</filter-name>
03 <filter-class>filters.ReDispatcherFilter</filter-class>
04 <init-param>
05 <param-name>includeServlets</param-name>
06 <param-value>JRPC</param-value>
07 <!--注:JRPC为下文配置的Servlet JSONRPCServlet过滤的请求配置 -->
08 </init-param>
09 </filter>
10 <filter-mapping>
11 <filter-name>JSONRPCServlet</filter-name>
12 <url-pattern>/*</url-pattern>
13 </filter-mapping>
14
15
16 <filter>
17 <filter-name>struts2</filter-name>
18 <filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>
19 </filter>
20 <filter-mapping>
21 <filter-name>struts2</filter-name>
22 <url-pattern>*.action</url-pattern>
23 </filter-mapping>
24
25 <filter-mapping>
26 <filter-name>struts2</filter-name>
27 <url-pattern>/*</url-pattern>
28 </filter-mapping>
29
30 <!--注：这里同样需要Servlet配置，Filter会转到该Servlet上-->
31 <servlet>
32 <servlet-name>JSONRPCServlet</servlet-name>
33 <servlet-class>
34 jcore.jsonrpc.servlet.JSONRPCServlet
35 </servlet-class>
36 <load-on-startup>2</load-on-startup>
37 </servlet>
38 <servlet-mapping>
39 <servlet-name>JSONRPCServlet</servlet-name>
40 <url-pattern>/JRPC</url-pattern>
41 </servlet-mapping>
过滤器的实现类:
view sourceprint?01 package filters;
02
03 import java.io.IOException;
04 import java.util.ArrayList;
05 import java.util.Arrays;
06
07 import javax.servlet.Filter;
08 import javax.servlet.FilterChain;
09 import javax.servlet.FilterConfig;
10 import javax.servlet.RequestDispatcher;
11 import javax.servlet.ServletException;
12 import javax.servlet.ServletRequest;
13 import javax.servlet.ServletResponse;
14 import javax.servlet.http.HttpServletRequest;
15
16 public class ReDispatcherFilter implements Filter {
17
18 public void destroy() {
19 // TODO Auto-generated method stub
20
21 }
22
23 public void doFilter(ServletRequest req, ServletResponse resp,
24 FilterChain chain) throws IOException, ServletException {
25
26 HttpServletRequest request = (HttpServletRequest) req;
27 String target = request.getRequestURI();
28 target = target.lastIndexOf("?") > 0 ? target.substring(target
29 .lastIndexOf("/") + 1, target.lastIndexOf("?")
30 - target.lastIndexOf("/")) : target.substring(target
31 .lastIndexOf("/") + 1);
32
33 //System.out.println(target);
34 if (this.includes.contains(target)) {
35 RequestDispatcher rdsp = request.getRequestDispatcher(target);
36
37 //System.out.println("go..............." + rdsp);
38 rdsp.forward(req, resp);
39 } else
40 chain.doFilter(req, resp);
41 }
42
43 private ArrayList<String> includes = new ArrayList<String>();
44
45 public void init(FilterConfig config) throws ServletException {
46
47 this.includes.addAll(Arrays.asList(config.getInitParameter(
48 "includeServlets").split(",")));
49
50 }
51