那么提示这样的错误是什么原因

08-03-18 studyjava
那么提示这样的错误是什么原因呢?请高人帮忙啊.

java.lang.NoSuchMethodError: org.apache.struts.config.ForwardConfig.getContextRelative()Z
org.apache.struts.tiles.TilesRequestProcessor.processForwardConfig(TilesRequestProcessor.java:302)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:229)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1858)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:459)
javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)

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ActionForward af = new ActionForward("success");
return af;
在return这块就出现错误页面了,这地方有什么不对的吗?很奇怪啊.