mvc -------- localhost登陆异常

Question

是不是本地电脑没有数据库，就写不了mvc

HTTP Status 500 – Internal Server Error

Type Exception Report

Description The server encountered an unexpected condition that prevented it from fulfilling the request.

Exception

java.lang.NullPointerException
com.lg.base.dao.BaseDao.selectSql(BaseDao.java:51)
com.lgdao.UserDao.loginSql(UserDao.java:41)
com.lg.controller.UserServlet.login(UserServlet.java:113)
com.lg.controller.UserServlet.doGet(UserServlet.java:38)
com.lg.controller.UserServlet.doPost(UserServlet.java:59)
javax.servlet.http.HttpServlet.service(HttpServlet.java:661)
javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
Note The full stack trace of the root cause is available in the server logs.

Apache Tomcat/8.5.37

Answer 1

你这是执行你的sql了呀com.lg.base.dao.BaseDao.selectSql(）,如果没有配置数据库，肯定报错呀，但是如果不执行数据库操作，是可以的