为什么我输入指定的用户名和密码后，总是无法跳转到登录成功的页面，只能到登录失败的页面？
代码如下：login.jsp&%@ page language="java" import="java.util.*" contentType="text/ charset=utf-8"%&&%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%&&!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"&&html&
&base href="&%=basePath%&"&
&title&My JSP 'login.jsp' starting page&/title&
&meta http-equiv="pragma" content="no-cache"& &meta http-equiv="cache-control" content="no-cache"& &meta http-equiv="expires" content="0"&
&meta http-equiv="keywords" content="keyword1,keyword2,keyword3"& &meta http-equiv="description" content="This is my page"& &!-- &link rel="stylesheet" type="text/css" href="styles.css"& --&
&div id="container"&
&div class="logo"&
&a href="#"&&img src="assets/logo.png" alt=""&&/a&
&div id="box"&
&form action="dologin.jsp" method="post"&
&p class="main"&
&label&用户名：&/label&
&input name="uername" value=""&
&label&密码：&/label&
&input name="password" type="password" value=""&
&p class="space"&
&input type="submit" value="登录" class="login" style="cursor: "&
&/body&&/html&dologin.jsp&%@ page language="java" import="java.util.*" contentType="text/ charset=utf-8"%&&%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; String username=""; String password=""; request.setCharacterEncoding("utf-8");
username=request.getParameter("username"); password=request.getParameter("password"); //username=request.getAttribute("username").toString(); //password=request.getAttribute("password").toString();
//如果用户名和密码都等于admin，则登录成功 if("abc".equals(username)&&"12345".equals(password)) {
request.getRequestDispatcher("login_success.jsp").forward(request,response);
response.sendRedirect("login_failure.jsp"); }%&login_success.jsp&%@ page language="java" import="java.util.*" contentType="text/ charset=utf-8"%&&%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%&&!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"&&html&
&base href="&%=basePath%&"&
&title&My JSP 'login.jsp' starting page&/title&
&%-- &meta http-equiv="pragma" content="no-cache"& &meta http-equiv="cache-control" content="no-cache"& &meta http-equiv="expires" content="0"&
&meta http-equiv="keywords" content="keyword1,keyword2,keyword3"& &meta http-equiv="description" content="This is my page"& --%& &link type="text/css" href="css/login.css" rel="stylesheet"/& &link type="text/css" href="css/smoothness/jquery-ui-1.7.2.custom.html" rel=""/& &script type="text/javascript" src="js/jquery 1.3.2.min.js"&&/script& &script type="text/javascript" src="js/easyTooltip.js"&&/script& &script type="text/javascript" src="js/jquery-ui-1.7.2.custom.min.js"&&/script& &!-- &link rel="stylesheet" type="text/css" href="styles.css"& --&
&div id="container"&
&div class="logo"&
&a href="#"&&img src="assets/logo.png"&&/a&
&div id="box"&
欢迎您XXX,登录成功！
&%--&font color="red"& --%&
&/body&&/html&login_failure.jsp&%@ page language="java" import="java.util.*" contentType="text/ charset=utf-8"%&&%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%&&!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"&&html&
&base href="&%=basePath%&"&
&title&My JSP 'login.jsp' starting page&/title&
&meta http-equiv="pragma" content="no-cache"& &meta http-equiv="cache-control" content="no-cache"& &meta http-equiv="expires" content="0"&
&meta http-equiv="keywords" content="keyword1,keyword2,keyword3"& &meta http-equiv="description" content="This is my page"& &!-- &link rel="stylesheet" type="text/css" href="styles.css"& --&
&div id="container"&
&div class="logo"&
&a href="#"&&img src="assets/logo.png"&&/a&
&div id="box"&
登录失败！请检查用户名或者密码！&br&
&a href="login.jsp"&返回登录&/a&
&/body&&/html&
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All Rights Reserved | 京ICP备 号-2关于登陆时输入正确的用户名和密码但是提示用户密码不对的问题
由于我是刚学java，对代码不太精通，所以看不出哪里出了问题，麻烦各位大神帮忙看看，谢谢~
&%@ page language="java" contentType="text/ charset=UTF-8" &&& pageEncoding="UTF-8"%& &!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" ""& &html& &head& &meta http-equiv="Content-Type" content="text/ charset=UTF-8"& &title&登陆页面&/title& &/head& &body& &center& 登陆界面 &/center&
&center& &form action="LoginServlet" method="post"& 用户名 &input type="text" name = "mname" /& &br&&br&&& 密码& &input type="password" name = "mpass"& &br& &input type = "submit" value = "提交"& &/form& &/center&
&/body& &/html&
welcom.jsp
&%@ page import ="java.util.*" contentType="text/ charset=gb2312" pageEncoding="gb2312"%& &!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" ""& &html& &head& &meta http-equiv="Content-Type" content="text/ charset=gb2312"& &title&登陆成功&/title&
&/head& &body& 欢迎你！登陆成功！&br&
&/body& &/html&
&%@ page language="java" contentType="text/ charset=UTF-8" &&& pageEncoding="UTF-8"%& &!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" ""& &html& &head& &meta http-equiv="Content-Type" content="text/ charset=UTF-8"& &title&登陆失败&/title& &/head& &body& 用户密码错误，单击 &a href="login.jsp"&这里&/a& 返回 &/body& &/html&
DBUtil.java
import java.sql.*;
public class DBUtil { boolean bInited = //加载驱动 public void initJDBC() throws ClassNotFoundException { //加载MYSQL JDBC驱动程序 Class.forName("com.mysql.jdbc.Driver"); bInited = System.out.println("Success loading Mysql Driver!");
public Connection getConnection() throws ClassNotFoundException, SQLException{ if(!bInited){ initJDBC(); } //连接URL为 jdbc:mysql//服务器地址/数据库名 //后面的2个参数分别是登陆用户名和密码 Connection conn = DriverManager.getConnection( "jdbc:mysql://localhost:3306/mybook","root","1111"); }
public boolean loginSuccess(String mname,String mpass){ boolean returnValue = String sql = "SELECT mname,mpass FROM guanli"; Connection conn = Statement stmt = ResultSet rs =
try{ conn = getConnection(); stmt = conn.createStatement(); rs = stmt.executeQuery(sql); while(rs.next()){ String MnameInDB = rs.getString("mname"); String MpassInDB = rs.getString("mpass"); if(MnameInDB.equals(mname) && MpassInDB.equals(mpass)){ returnValue = } } }catch (ClassNotFoundException e) { e.printStackTrace(); }catch (SQLException e) { e.printStackTrace(); }
return returnV
LoginServlet.jsp
import java.io.IOE
import javax.servlet.ServletC import javax.servlet.ServletE import javax.servlet.ServletR import javax.servlet.ServletR import javax.servlet.http.HttpServletR import javax.servlet.http.HttpServletR import javabean.DBU
public class LoginServlet implements javax.servlet.Servlet{
public void destroy() {
public ServletConfig getServletConfig() { }
public String getServletInfo() { }
public void init(ServletConfig arg0) throws ServletException {
public void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException{ String Mname = request.getParameter("mname");//取得用户名 String Mpass = request.getParameter("mpass");//取得密码 DBUtil db = new DBUtil();//构建数据库对象 boolean canLogin = db.loginSuccess(Mname, Mpass); if(canLogin){//根据登陆情况，跳转页面 response.sendRedirect("welcome.jsp"); }else{ response.sendRedirect("back.jsp"); } } public void service(ServletRequest request, ServletResponse response) throws ServletException, IOException { HttpServletRequest rq = (HttpServletRequest) HttpServletResponse rs = (HttpServletResponse) doPost(rq,rs); }
web.xml配置
&?xml version="1.0" encoding="UTF-8"?&
&web-app version="2.4"
xmlns:xsi=""
xsi:schemaLocation="
&servlet-name&LoginServlet&/servlet-name&
&servlet-class&servlet.LoginServlet&/servlet-class&
&/servlet&
&servlet-mapping&
&servlet-name&LoginServlet&/servlet-name&
&url-pattern&/login&/url-pattern&
&/servlet-mapping&
&welcome-file-list&
&welcome-file&login.jsp&/welcome-file&
&/welcome-file-list&
&/web-app&
loginSuccess方法中肯定有异常被捕获，returnValue赋值语句，没有执行到。
贴代码时贴重点部分就可以了，另外验证帐号是否正确 &直接用where语句条件查询不就完了 &何必将整个表的数据都搞出来，遍历结果集。
针对你当前这个问题 &你应该debug你那个while语句 &
粘贴代码的时候，可以选择格式。
在loginsucess里debug下不就行了，但是为什么你要写个循环呢？直接用条件去查不是更好？另外。。照片中是你本人吗}