数据库test 中建个表 stu(stuid 主键 自动增长 ，用户名，密码，年龄)
1.设计一个注册页面，实现用户注册功能
2.设计一个登陆页面，实现用户名密码登陆
3.两个页面可以互相超链接
package lcx;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class l {
public void regUser(User user) {
String sql = "insert into stu(uname,password,age) value(?,?,?)";
Connection cn = null;
PreparedStatement ps = null;
// 创建连接
cn = llcx.getCon();
try {
// 预编译
ps = cn.prepareStatement(sql);
// 替换占位符‘？’
ps.setString(1, user.getUname());
ps.setString(2, user.getPassword());
ps.setInt(3, user.getAge());
// 编译执行sql语句
ps.executeUpdate();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
try {
ps.close();
cn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public User getUserByName(String uname) {
String sql = "select * from stu where uname=?";
Connection cn = null;
PreparedStatement ps = null;
ResultSet res = null;
User user = null;
cn = llcx.getCon();
try {
ps = cn.prepareStatement(sql);
ps.setString(1, uname);
res = ps.executeQuery();
if (res.next()) {
user = new User(res.getString("uname"), res.getString("password"), res.getInt("age"));
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
try {
ps.close();
cn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return user;
}
}
package lcx;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class llcx {
static {
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static Connection getCon() {
Connection cn = null;
try {
cn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "123456");
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return cn;
}
}
package lcx;
public class User {
private Integer stuId;
private String uname;
private String password;
private Integer age;
public User(String uname, String password, Integer age) {
super();
this.uname = uname;
this.password = password;
this.age = age;
}
public User() {
super();
}
public String getUname() {
return uname;
}
public void setUname(String uname) {
this.uname = uname;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Integer getStuId() {
return stuId;
}
public void setStuId(Integer stuId) {
this.stuId = stuId;
}
}
<%@ page language="java" import="java.util.*" pageEncoding="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>
<head>
<title>My JSP 'register.jsp' starting page</title>
</head>
<body>
<form action="index3.jsp" method="post">
用户名:<input type="text" name="uname"><br>
密 码: <input type="password" name="password"> <br>
年 龄:<input type="text" name="age"><br>
<input type="submit" value="注册"><hr>
</form><hr>
<a href="index1.jsp">返回登录</a>
</body>
</html>
<%@ page language="java" import="java.util.*" pageEncoding="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>
<head>
<title>My JSP 'login.jsp' starting page</title>
</head>
<body>
<script type="text/javascript">
function validate() {
if (loginForm.uname.value == "") {
alert("账号不能为空!");
return;
}
if (loginForm.password.value == "") {
alert("密码不能为空!");
return;
}
loginForm.submit();
}
</script>
<form name="loginForm" action="index2.jsp" method="post">
用户名:<input type="text" name="uname"><br>
密 码: <input type="password" name="password"> <br>
<input type="button" value="登录" onclick="validate()"><hr>
</form>
<hr>
<a href="index.jsp">返回注册</a>
</body>
</html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ page import="com.ym.mysql.User" %>
<%@ page import="com.ym.mysql.StuDao" %>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'index2.jsp' starting page</title>
</head>
<body >
<%
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
String uname = request.getParameter("uname");
String password = request.getParameter("password");
StuDao stuDao = new StuDao();
User user = stuDao.getUserByName(uname);
if (password.equals(user.getPassword())) {
response.sendRedirect("index5.jsp");
} else {
response.sendRedirect("index6.jsp");
}
%>
</body>
</html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ page import="lcx.User" %>
<%@ page import="lcx.l" %>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'index3.jsp' starting page</title>
</head>
<body>
<%
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
String uname=request.getParameter("uname");
String password=request.getParameter("password");
Integer age=Integer.parseInt(request.getParameter("age"));
User user=new User(uname,password,age);
l l=new l();
l.regUser(user);
response.sendRedirect("index1.jsp");
%>
</body>
</html>
<%@ page language="java" import="java.util.*" pageEncoding="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>
<head>
<title>My JSP 'index4.jsp' starting page</title>
</head>
<body>
<h1>登录成功！！！</h1>
</body>
</html>
<%@ page language="java" import="java.util.*" pageEncoding="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>
<head>
<title>My JSP 'index5.jsp' starting page</title>
</head>
<body>
<h1>登录失败！3秒后将返回登录界面。。。</h1>
<%
response.setHeader("refresh", "3;url=index1.jsp");
%>
</body>
</html>
