com.stbook.struts.BeanActionException: 调用Bean的相应Action方法出错: ('viewProduct'). Cause: java.lang.reflect.InvocationTargetException Caused by: java.lang.reflect.InvocationTargetException at com.stbook.struts.BeanAction.execute(BeanAction.java:138) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397) at javax.servlet.http.HttpServlet.service(HttpServlet.java:689) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java: