1.新建mysql数据库 create database spring;
切换数据库 use spring;
新建表 create table user (id int(3) auto_increment not null primary key,username varchar(20),password varchar(20));
2.写程序
<%@ page language="java" import="java.util.*, java.sql.*" pageEncoding="UTF-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; String username = request.getParameter("username"); String password = request.getParameter("password"); String password2 = request.getParameter("password"); Class.forName("com.mysql.jdbc.Driver"); Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/spring","root","123456"); String sqlQuery = "select count(*) from user where username = ?"; PreparedStatement psQuery = conn.prepareStatement(sqlQuery); psQuery.setString(1, username); ResultSet rs = psQuery.executeQuery(); rs.next(); int count = rs.getInt(1); if (count > 0 ){ response.sendRedirect("registerFail.jsp"); psQuery.close(); conn.close(); return ; } String sql = "insert into user values(null, ? ,? )"; PreparedStatement ps = conn.prepareStatement(sql); ps.setString(1, username); ps.setString(2, password); ps.executeUpdate(); ps.close(); conn.close(); response.sendRedirect("registerSuccess.jsp"); %>
4. 在register.jsp中展示
<body> <form method="post" action="registerDeal.jsp"> 用户名: <input type="text" name="username"><br> 密码: <input type="password" name="password"><br> 确认密码: <input type="password" name="password"><br> <input type="submit" value="提交"> </form> </body>
添加User和UserManager类，实现deal.jsp中的功能
1. com.liu.registration.model
package com.liu.registration.model;
public class User {
int id;
String username;
String password;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
2.com.liu.registration.service
package com.liu.registration.service;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import com.liu.registration.model.User;
public class UserManager {
public boolean exists(User u) throws Exception{
Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/spring","root","123456");
String sqlQuery = "select count(*) from user where username = ?";
PreparedStatement psQuery = conn.prepareStatement(sqlQuery);
psQuery.setString(1, u.getUsername());
ResultSet rs = psQuery.executeQuery();
rs.next();
int count = rs.getInt(1);
psQuery.close();
conn.close();
System.out.println("count = " + count);
if (count > 0 ){
return true;
} else{
return false;
}
}
public void add(User u) throws Exception{
Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/spring","root","123456");
String sql = "insert into user values(null, ? ,? )";
PreparedStatement ps = conn.prepareStatement(sql);
ps.setString(1, u.getUsername());
ps.setString(2, u.getPassword());
ps.executeUpdate();
ps.close();
conn.close();
}
}
总结
