解决方案:没有指定参数
String user = req.getParameter("user");
String pwd = req.getParameter("pwd");
Connection conn = DbUtil.getCon();
String sql = "select name from user where name=? and password=?";
PreparedStatement pst = conn.prepareStatement(sql);
pst.setString(1, user);
pst.setString(2, pwd);
问题:java.sql.SQLException: No value specified for parameter 1
原文：http://www.cnblogs.com/a1045417817/p/7550891.html