Java不注册consul 用户注册java

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mob64ca1404476b 2023-08-16 22:30:50

文章标签 Java不注册consul javaweb java html css 文章分类 Java 后端开发

用户注册登录过程主要分为几个步骤：（1）前端页面设计；（2）数据访问模型包；（3）Servlet容器数据接收处理；（4）跳转至页面。下面分步骤小记一下，供以后参考：

整个实现环境：Eclipse Version: 2018-09 (4.9.0)--Eclipse Java EE IDE for Web Developers.；JDK 1.8.0_73；mysql：5.6.44-win32（远程数据库）；Tomcat9.0

项目结构如下：

Java不注册consul 用户注册java_java

（1）前端页面设计

由于仅仅是用户注册登录，因此设计就较为简单。在Eclipse中新建Dynamic web project，并命名为new。WebContent用于存放页面设计文档，如结构图中的front目录为前端页面文档，包括css、img和jsp文件。其上一级目录中的index.jsp仅为跳转使用，前端页面首页为front目录下的index.jsp。如下首页代码，资源文件如css和img可以不管，重点是实现的过程。

首页代码参考：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>  
<meta http-equiv="content-type" content="text/html" charset="GB2312">
<title>myweb</title>
<link rel="stylesheet" type="text/css" href="css/front.css">
</head>
<body>
 
<div class="box1">
<div class="header">
<li><a href="user.jsp">公司简介</a></li>
<li><a href="news.html">公司新闻</a></li>
<!--  如果session中username的值存在，则显示欢迎用户 和用户退出-->
<% if(request.getSession().getAttribute("username")!=null){ %>

 <li>welcome,<%=request.getSession().getAttribute("username")%></li>
  <li><a href="logout.jsp">用户退出</a></li>
 <% } else{ %>
 <!--  如果session中username的值不存在，则显示用户注册 和用户登录-->
 <li><a href="register.jsp">用户注册</a></li>
<li><a href="login.jsp">用户登录</a></li>
 <% } %>
</div>
<div class="main">
 <img src="img/car.jpg">
</div>
</div>

Java不注册consul 用户注册java_css_02

用户注册register.jsp代码：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<link rel="stylesheet" type="text/css" href="css/front.css">
</head>
<body>
<div class="box">
  <form action="UserRegister" method="post">
   <div class="section">
     <label>username</label>
     <input type="text" name="username">   
   </div>
    <div class="section">
     <label>username</label>
     <input type="password" name="userpwd">   
   </div>
   <div class="section">
     <label>gender</label>
     <input type="radio" name="sex"> male  
     <input type="radio" name="sex"> female
   </div>
      <div class="section">
     <input type="submit" name="submit" value="提交">
     <input type="reset" name="reset" value="Reset">   
   </div>
   </form>
</div>
</body>
</html>

用户登录login.jsp代码：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<link rel="stylesheet" type="text/css" href="css/front.css">
</head>
<body>
<div class="box">
  <form action="UserServlet" method="post">
   <div class="section">
     <label>username</label>
     <input type="text" name="username">   
   </div>
    <div class="section">
     <label>username</label>
     <input type="password" name="userpwd">   
   </div>
      <div class="section">
     <input type="submit" name="submit" value="提交">
     <input type="reset" name="reset" value="Reset">   
   </div>
   </form>
</div>
</body>
</html>

用户退出logout.jsp代码：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<% request.getSession().setAttribute("username", null); %>
<script>
  window.location.href="index.jsp";
</script>
</body>
</html>

用户登录和用户注册在前端页面处都是表单样式，这里form表单里的action指向了servlet容器，servlet容器用于处理http请求如表单提交request以及响应response反馈给页面。

（2）DAO数据访问模型对象

这里的DAO是数据访问对象包简写，本次还未涉及使用任何框架。在java Resources里新建一个dao包，（新建package），然后在该包里新建两个java类，一个是负责连接数据库和关闭数据库的封装类DButils.java，一个是负责与数据库交互处理如新增、删除、更新、查询等操作的类，这里名为为LoginDaolmp.java，即用于处理用户登录和注册的数据模型类。

DButils.java类代码如下：

package dao;
import java.sql.*;
public class DButils {	 
		static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";  
	    static final String DB_URL = "jdbc:mysql://106.13.111.246:3306/new";		
	    static final String USER = "cao";
	    static final String PASS = "root123";
	    static Connection conn = null;
	    
	    public static Connection getConnection(){ 
	        try {
	            //加载oracle驱动
	            Class.forName(JDBC_DRIVER);
	            //通过驱动获取数据库的连接
	            conn  = DriverManager.getConnection(DB_URL,USER,PASS);
	            System.out.println("连接成功");
	        } catch (Exception e) {
	            // TODO Auto-generated catch block
	            e.printStackTrace();
	        }
	        return conn;
	    }
	    
	    public static void Close(){
	        try { 
	        	if(conn!=null) {	            	  
	                  conn.close();
	            }

	        } catch (SQLException e) {
	            // TODO: handle exception
	        	 e.printStackTrace();
	        }
	    }	
}

LoginDaolmp.java代码如下：

package dao;
import java.sql.*;
public class LoginDaolmp {
  
//登录时查询用户名和密码是否匹配，如果匹配则返回真	
	public boolean searchName(String loginName, String loginpwd) {
		Connection conn=(Connection)DButils.getConnection();
		String sql="select * from user where username=? and userpwd=?";
		try {
			PreparedStatement ps=(PreparedStatement)conn.prepareStatement(sql);
			ps.setString(1, loginName);
			ps.setString(2,loginpwd);
			ResultSet rs=ps.executeQuery();
			while(rs.next()) {
				return true;
			}
		} catch (SQLException e) {
            // TODO: handle exception
        	 e.printStackTrace();
	    }
		return false;
	
	}
	//注册时将新用户名和信息插入数据库，操作成功则返回真	
	public boolean RegisterName(String loginName, String loginpwd,String sex) {
		Connection conn=(Connection)DButils.getConnection();
		PreparedStatement ps=null;
		String sql="insert into user values(null,?,?,?)";
		try {			 
			ps=conn.prepareStatement(sql);
			ps.setString(1, loginName);
			ps.setString(2,loginpwd);
			ps.setString(3, sex);
			int result=ps.executeUpdate(); 
			if(result==1) {
			return true;}
			 
		} catch (SQLException e) {
            // TODO: handle exception
        	 e.printStackTrace();
	    }
		 return false;	
	}
}

（3）Servlet容器接收响应处理

当进入首页点击用户登录或用户注册时，表单响应会提交至servlet容器。操作时新建servlet容器，然后新建两个类，一个为处理用户登录，一个为处理用户注册。这里分别命名为UserRegister和UserServlet，如下为处理用户登录的UserServlet类代码：

package Servlet;
import java.io.IOException;
import java.io.PrintWriter;
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 dao.LoginDaolmp;

/**
 * Servlet implementation class UserServlet
 */
@WebServlet("/front/UserServlet")
public class UserServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public UserServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.getWriter().append("Served at: ").append(request.getContextPath());
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
		String username=request.getParameter("username"); //获取表单里用户名文本框信息
		String userpwd=request.getParameter("userpwd");//获取表单里用户密码文本框信息
		LoginDaolmp dl=new LoginDaolmp(); 
		PrintWriter out=response.getWriter();
		boolean isHave=dl.searchName(username, userpwd);//调用查询用户名和密码是否匹配方法
		if(isHave) {
			response.setCharacterEncoding("UTF-8");
			response.setContentType("text/html;charset=utf-8");
			request.setAttribute("username", username);	 	
			request.getSession().setAttribute("username", username); //将登录用户名保存在session里
           out.println("<script>alert('登录成功！');window.location.href='index.jsp'</script>");
		}else {
			request.getSession().setAttribute("info", "account does not right");  	
			response.sendRedirect("index.jsp");
		}		
	}

}

如下为处理用户注册的UserRegister类代码：

package 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 dao.LoginDaolmp;

/**
 * Servlet implementation class UserRegister
 */
@WebServlet("/front/UserRegister")
public class UserRegister extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public UserRegister() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.getWriter().append("Served at: ").append(request.getContextPath());
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		String username=request.getParameter("username");
		String userpwd=request.getParameter("userpwd");
		String sex=request.getParameter("sex");
		LoginDaolmp dl=new LoginDaolmp();
		boolean isHave=dl.RegisterName(username, userpwd, sex);
		if(isHave) {
			request.setAttribute("username", username);
			System.out.println("注册成功！");
			request.getRequestDispatcher("index.jsp").forward(request, response);
		}else {
			request.getSession().setAttribute("info", "account does not right");
			response.sendRedirect("front/register.jsp");
		}
	}
}

可以看到在servlet容器里两个类主要编写的是doPost方法，在doPost方法里处理用户注册和登录。

（4）测试效果

当点击首页的用户登录后，进入登录表单页面，填写用户名和密码，点击提交后就会进入UserServlet类进行用户信息匹配操作处理，如果返回为真，则将用户名信息保存到session里，首页页面显示的就是欢迎用户信息了。如下：

Java不注册consul 用户注册java_javaweb_03