这个异常，The server encountered an internal error () that prevented it from fulfilling this request.

HTTP Status 500 -type Exception reportmessagedescription The server encountered an internal error () that prevented it from fulfilling this request.exceptionorg.apache.jasper.JasperException: java.lang.NullPointerException
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:522)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:416)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:416)root causejava.lang.NullPointerException
org.apache.struts2.components.UIBean.evaluateParams(UIBean.java:746)
org.apache.struts2.components.UIBean.end(UIBean.java:481)
org.apache.struts2.views.jsp.ComponentTagSupport.doEndTag(ComponentTagSupport.java:43)
org.apache.jsp.index_jsp._jspx_meth_s_005ftextfield_005f0(index_jsp.java:158)
org.apache.jsp.index_jsp._jspx_meth_s_005fform_005f0(index_jsp.java:117)
org.apache.jsp.index_jsp._jspService(index_jsp.java:76)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:416)note The full stack trace of the root cause is available in the Apache Tomcat/6.0.18 logs.