SQL登录注册练习

/class User

package com.neusoft.bean;

public class User {
   private  int password;
   private  String name;

	public User() {
		super();
		// TODO Auto-generated constructor stub
	}
	public User(int password, String name) {
		super();
		this.password = password;
		this.name = name;
	}

	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getPassword() {
		return password;
	}
	public void setPassword(int password) {
		this.password = password;
	}
	@Override
	public String toString() {
		return "password=" + password + ", name=" + name;
	}
   
	
}

　　/class LoginDao

package com.neusoft.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import com.neusoft.bean.User;
import com.neusoft.bean.UserRegist;
import com.neusoft.utils.JDBCUtil;

public class LoginDao {
     public User getUser(String name,String password){
    	 User user=null;    	
    	 PreparedStatement ps=null;
    	 ResultSet rs =null;
    	 Connection conn=JDBCUtil.getConnection();
    	 String sql="select * from t_user where password= ? and name =?";
    	 try {
    		  ps = conn.prepareStatement(sql);
              ps.setString(1, password);
              ps.setString(2, name);
              rs = ps.executeQuery();
			if (rs.next()) {
				String username = rs.getString("name");
				int password2 = rs.getInt("password");
				user=new User(password2,username);
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally {			
			JDBCUtil.close(ps, rs, conn);
		}
		return user;
    	 
     }
     public void Add(String name,String password,String email){

    	 PreparedStatement ps=null;
    	 Connection conn=JDBCUtil.getConnection();
    	 String sql="insert into t_user values(?,?,?,?)";
    	 try {
    		  ps = conn.prepareStatement(sql);
              ps.setString(1, null);              
              ps.setString(2, name);
              ps.setString(3, password);
              ps.setString(4, email);
               ps.executeUpdate();
			System.out.println(ps.toString());
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally {			
			
			if (ps !=null) {
				try {
					ps.close();
				} catch (SQLException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
			if (conn !=null) {
				 try {
					conn.close();
				} catch (SQLException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		}	 
     }
     public void Update(String name,String password,String email){

    	 PreparedStatement ps=null;
    	 Connection conn=JDBCUtil.getConnection();
    	 String sql="update t_user set name=?,pasword=?,mail=? where id=?";
    	 try {
    		  ps = conn.prepareStatement(sql);
              ps.setString(1, null);              
              ps.setString(2, name);
              ps.setString(3, password);
              ps.setString(4, email);
               ps.executeUpdate();
			System.out.println(ps.toString());
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally {			
			
			if (ps !=null) {
				try {
					ps.close();
				} catch (SQLException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
			if (conn !=null) {
				 try {
					conn.close();
				} catch (SQLException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		}	 
     }
}

　　/class LoginServlet

package com.neusoft.servlet;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.neusoft.bean.User;
import com.neusoft.dao.LoginDao;

@WebServlet("/LoginServlet")
public class LoginServlet extends HttpServlet {
	private static final long serialVersionUID = 1L; 
	
	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		String name = request.getParameter("username");
		String psd = request.getParameter("pwd");
		User user=new LoginDao().getUser(name, psd);
		if (user !=null) {
			List<User>List=new ArrayList<User>();
			List.add(user);
			request.setAttribute("stuList", List);
			//response.sendRedirect("Login-yes.html");//重定向
			request.getRequestDispatcher("/login-success.jsp").forward(request, response);//转发
		}else {
			request.getRequestDispatcher("/Login-no.html").forward(request, response);//转发
		}
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		
		doGet(request, response);
//		request.setCharacterEncoding("utf-8");//第一次传参之前设置编码格式
//		response.setContentType("text/html;charset=utf-8");
//		response.setHeader("Content-Type", "text/html;charset=utf-8");
//		response.getWriter().println("");
	}

}

　　/class RegistServlet

package com.neusoft.servlet;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.neusoft.bean.User;
import com.neusoft.dao.LoginDao;
@WebServlet("/RegistServlet")
public class RegistServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		request.setCharacterEncoding("utf-8");
		String name = request.getParameter("username");
		String psd = request.getParameter("pwd");
		String psd2 = request.getParameter("pwd2");
		String email = request.getParameter("email");
		User user=new LoginDao().getUser(name, psd);
		if (user != null) {
			request.getRequestDispatcher("/Regist-error.html").forward(request, response);//转发
		}else if (psd2.equals(psd)) {
			response.setHeader("Content-Type", "text/html;charset=utf-8");
			new LoginDao().Add( name, psd, email);			
			response.sendRedirect("/Regist-success.html");//重定向
		}
		
	}

}

　　/class JDBCUtil

package com.neusoft.utils;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class JDBCUtil {
	private static String driver="com.mysql.jdbc.Driver";
	private static String url="jdbc:mysql://localhost:3306/demo";
	private static String username="root";
	private static String password="123456";
	static{
		
		try {
			Class.forName(driver);			
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
	}
	public static Connection getConnection(){
			try {
				return DriverManager.getConnection(url, username, password);
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				return null;
			}
		}
	
	public static void close(Statement st,ResultSet rs,Connection conn){
		if (conn !=null) {
			 try {
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		if (rs !=null) {
			try {
				rs.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		if (st !=null) {
			try {
				st.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}
}

　　Login.html

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
   <form action="/TestLogin/LoginServlet" method="get">
                   用户名：<input type="text" name="username"/>
                   密码：<input type="password" name="pwd"/>
       <input type="submit" value="提交"/>
   </form>
   <a href="Regist.html">去注册</a>
</body>
</html>

/login-success.jsp

<%@page import="com.neusoft.bean.User"%>
<%@page import="java.util.ArrayList"%>
<%@page import="java.util.List"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
   <table border="1" align="center" width="50%">
      <tr>
         <th>姓名 </th>
         <th>密码 </th>
         <th colspan="2"> </th>
      </tr>
      <% 
      List<User>stuList=new ArrayList<User>();
      stuList=(List<User>)request.getAttribute("stuList");
      for(int i=0;i<stuList.size();i++){
          User user=stuList.get(i);
          %>
            <tr>
             <td><%=user.getName() %></td>
             <td><%=user.getPassword() %></td>
             <td><a href="#">修改</a></td>
             <td><a href="#">删除</a></td>
            </tr>
          <%
         }
      %>
      
   </table>
</body>
</html>

Regist.html

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
   <form action="/TestLogin/RegistServlet" method="post">
                   用户名：<input type="text" name="username"/><br>
                   密码：<input type="password" name="pwd"/><br>
                    确认密码：<input type="password" name="pwd2"/><br>
                     邮箱：<input type="text" name="email"/><br>
       <input type="submit" value="提交"/>
   </form>
</body>
</html>

其他的就不传了，就一行代码，还有就是导包

这次是在这