java web实现注册登陆

页面效果

点击访问该页面

图解分析

通过工具类连接mysql数据库，之后可以直接调用，避免重复写代码，通过servlet将用户注册信息存入数据库，登陆时查询校验，从而实现登陆。

至于具体的页面校验没写，以后补充，毕竟正则也忘得差不多了，后面再补回来

源码

工具类

DBconnect.java

package com.yolin.tools;
import java.sql.*;

public class DBconnect {
	public Connection getconn(){
		Connection conn=null;
		try {
			Class.forName("com.mysql.jdbc.Driver");
			conn=(Connection) DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/test","root","123456");
		} catch (Exception e) {
			e.printStackTrace();
		}
		return conn;
	}
}

注册的servlet实现

DBregister.java

package com.yolin.tools;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import java.sql.*;
public class DBregister extends HttpServlet {

	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.setContentType("text/html;charset=utf-8");
		String username=request.getParameter("username");  //网页发送过来的用户名
		String password=request.getParameter("password");   //密码
		System.out.println(username+" "+password);
		String sql="insert into login values('"+username+"','"+password+"');";
		DBconnect db=new DBconnect();
		Connection conn=db.getconn();
		try {
			Statement stat=conn.createStatement();
			stat.execute(sql);	
			response.getWriter().println("<h1 align='center'>注册成功，2秒后跳转登陆页面</h1>");
			response.setHeader("Refresh","2;url=/web_test/login1.html");
			stat.close();
			conn.close();
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
}

登陆的servlet实现

DBdemo1.java

package com.yolin.tools;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.*;

public class DBdemo1 extends HttpServlet {
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {	
	}
	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		response.setContentType("text/html;charset=utf-8");
		String username=request.getParameter("username");  //网页发送过来的用户名
		String password=request.getParameter("password");   //密码
		System.out.println(username+" "+password);
		String sql="select password,username from login where username="+"'"+username+"'";
		String pwd="";
		String usr="";
		try {
			DBconnect db=new DBconnect();
			Connection conn= db.getconn();
			System.out.println(conn);   //查看数据库是否连接成功
			Statement stat=conn.createStatement(); //获取sql语句执行对象
			//stat.executeQuery(sql);
			ResultSet res=stat.executeQuery(sql);
			while(res.next()){
				System.out.println(res.getString(1)+""+res.getString(2));  //查询该数据库中的密码
				pwd=res.getString(1);	
				usr=res.getString(2);
			}
			if(usr==""){
				response.getWriter().println("<h1 align='center'>用户不存在，即将返回</h1>");
			    response.setHeader("Refresh", "2;url=/web_test/login1.html");
			    }else
			if(password.equals(pwd)){
				System.out.println("密码正确");
				response.getWriter().println("<h1 align='center'>密码正确，登录成功，2秒后跳转主页</h1>");
				response.setHeader("Refresh","2;url=/web_test/success1.html");
			}else{
				System.out.println("密码错误");
				response.getWriter().println("<h1 align='center'>密码错误，登录失败，即将返回</h1>");
				response.setHeader("Refresh", "2;url=/web_test/login1.html");
			}		
			stat.close();
			conn.close();
		} catch (Exception e) {		
			e.printStackTrace();
		}	
	}
}

三个html页面

3个html页面已经打包，需要的话直接下载吧

登陆_注册_成功页面.rar