求一个懂 java 的大神帮忙解决一个问题

V2EX = way to explore

V2EX 是一个关于分享和探索的地方

现在注册

已注册用户请登录

这是一个创建于 2877 天前的主题，其中的信息可能已经有所发展或是发生改变。

首页 index.jsp 页面报错

Error:java.lang.NullPointerException

后台登录完报错为

HTTP Status 500 - An exception occurred processing JSP page /admin/sys/loginpost.jsp at line 28

type Exception report

message An exception occurred processing JSP page /admin/sys/loginpost.jsp at line 28

description The server encountered an internal error that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: An exception occurred processing JSP page /admin/sys/loginpost.jsp at line 28

25: String lang = Request.GetString("lang", "chinese"); 26: 27: UserLogin userLogin = new UserLogin(dbo, session, "AdminLogin", request); 28: if(userLogin.Login(name, password, 1)) 29: { 30: WebInit.Init_Lang = lang;//chinese english 31: response.sendRedirect("/admin/main.html");

Stacktrace: org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:568) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:470) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334) javax.servlet.http.HttpServlet.service(HttpServlet.java:727) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) root cause

java.lang.NullPointerException com.NJD.db.DBO.ExecuteQuery(wd:171) com.NJD.db.mysql.MySQL5_5.GetRecordsNum(bd:219) com.NJD.ums.basic.UserDb.Exist(cc:198) com.NJD.ums.UserLogin.Login(wb:193) org.apache.jsp.admin.sys.loginpost_jsp._jspService(loginpost_jsp.java:94) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:727) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334) javax.servlet.http.HttpServlet.service(HttpServlet.java:727) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

11 条回复 • 2017-01-08 23:43:55 +08:00

zjw60320

2017-01-06 13:40:07 +08:00

空指针，看一下 /admin/sys/loginpost.jsp at line 28 这里有什么问题

holyghost

2017-01-06 13:41:48 +08:00

不是大神，不懂 java ，但是难道不应该去看看 28: if(userLogin.Login(name, password, 1)) 哪里可能会 NPE 吗？

（一个猜想不一定对

Melissa

2017-01-06 13:44:59 +08:00

@zjw60320 感觉这个地方没有什么问题啊~~

<%
DBO dbo = new DB().getDbo();
dbo.setRequest(request);
//DBO dbo = new MySQL5_5(WebInit.Init_DefaultDB);
RequestHandle Request = new RequestHandle(request);
String htmlStr = "";

String name = Request.GetString("user", true);
String password = Request.GetString("pwd", true);
String code = Request.GetString("code");
String lang = Request.GetString("lang", "chinese");

UserLogin userLogin = new UserLogin(dbo, session, "AdminLogin", request);
if(userLogin.Login(name, password, 1))
{
WebInit.Init_Lang = lang;//chinese english
response.sendRedirect("/admin/main.html");
}
else
{
htmlStr = "<script>";
htmlStr += "ReturnError('"+ userLogin.getErrorMsg() +"');";
htmlStr += "</script>";
out.print(htmlStr);
}

dbo.CloseAll();
%>