我把错误提示贴出,本人真的不知道错误出现在哪个地方,请大家帮忙看看type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception javax.servlet.ServletException
org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:516)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:423)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
cn.com.tym.filter.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117)
root cause java.lang.NullPointerException
StudyBbs.DB.<init>(DB.java:16)
StudyBbs.LoginAction.execute(LoginAction.java:31)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
cn.com.tym.filter.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117)
note The full stack trace of the root cause is available in the Apache Tomcat/5.0.30 logs.
org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:516)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:423)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
cn.com.tym.filter.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117)
root cause java.lang.NullPointerException
StudyBbs.DB.<init>(DB.java:16)
StudyBbs.LoginAction.execute(LoginAction.java:31)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
cn.com.tym.filter.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117)
note The full stack trace of the root cause is available in the Apache Tomcat/5.0.30 logs.
java.lang.NullPointerException
你去看看
StudyBbs.DB. <init>(DB.java:16)
StudyBbs.LoginAction.execute(LoginAction.java:31)
这里传值之前有没有尚未被实例化的变量
StudyBbs.DB. <init>(DB.java:16)
StudyBbs.LoginAction.execute(LoginAction.java:31)
很明显的空指针异常
你检查一下DB.java:16和LoginAction.java:31这两个地方代码
建议楼主养成良好的编码习惯,调用之前先判断一下是否为null。
这个地方报的错,你去看一下,是不是有个地方没有得到值
StudyBbs.LoginAction.execute(LoginAction.java:31)
点击一下就到出错位置了
StudyBbs.LoginAction.execute(LoginAction.java:31)
原因在这里,看看有没有实例化对像
java.lang.NullPointerException
StudyBbs.DB. <init>(DB.java:16)
StudyBbs.LoginAction.execute(LoginAction.java:31)
--------------------------
execute()取不出数值
java.lang.NullPointerException
你去看看
StudyBbs.DB. <init>(DB.java:16)
StudyBbs.LoginAction.execute(LoginAction.java:31)
这里传值之前有没有尚未被实例化的变量