javaWeb連接數據庫實現簡單登陸註冊功能的全過程

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實現步驟

創建maven項目 配置Tomcat 這些都不細說瞭

jar包

因為要連接數據庫所以一定要在maven項目下的xml文件下配置數據庫的jar包依賴

    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>8.0.28</version>
    </dependency>

這個千萬不要忘瞭 重重之重

數據庫的驅動以及用戶密碼

package com.li.Servlet.blit;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

public class JDBC {
    private static String url = null;
    private static String name = null;
    private static String password = null;

    static {
        try {
            Class.forName ( "com.mysql.cj.jdbc.Driver" );
        } catch (Exception e) {
            e.printStackTrace ( );
        }
        url = "jdbc:mysql://localhost:3306/zhiqingli?useUnicode=true&characterEncoding=utf8&useSSL=true";
        name = "root";
        password = "root";
    }

    public static Connection getConn() throws Exception {
        return DriverManager.getConnection ( url, name, password );
    }

    public static void release(Connection conn, PreparedStatement pst, ResultSet res) {
        try {
            if (res != null) {
                res.close ( );
            }
            if (pst != null) {
                pst.close ( );
            }
            if (conn != null) {
                conn.close ( );
            }
        } catch (Exception e) {
            e.printStackTrace ( );
        }
    }
}

這個類可以直接復制使用，但要改成自己的數據庫名字

jsp頁面

登陸頁面

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<body>
<form action="${pageContext.request.contextPath}/test" method="get">
   <h3>賬號：<input type="text" name="account"></h3>
   <h3>密碼：<input type="password" name="paw"></h3>
   <h3><input type="submit" value="登陸"><a href="Register.jsp" rel="external nofollow"  target="_blank">註冊</a></h3>
</form>
</body>
</html>

註冊頁面

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
   <title>註冊</title>
</head>
<body>
<form action="${pageContext.request.contextPath}/res" method="post">
   <h3>賬號：<input type="text" placeholder="請輸入註冊的賬號" name="number"></h3>
   <h3>密碼：<input type="password" placeholder="請輸入註冊的密碼" name="word" id="one"></h3>
   <h3>確認密碼：<input type="password" placeholder="確認一遍密碼" name="u" id="two"></h3>
   <input type="submit" value="提交" οnclick="show()">
</form>
<Script>
function show(){
    var one = document.getElementById("one").value;
    var two = document.getElementById("two").value;
    if (one === two){
        alert("註冊成功");
        window.open("index.jsp")
    }else {
        alert("兩次輸入的密碼不一致");
    }
}
</Script>
</body>
</html>

登陸成功和失敗的頁面

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
  <title>成功頁面</title>
</head>
<body>
<h1>登陸成功，感謝使用</h1>
</body>
</html>

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
  <title>失敗頁面</title>
</head>
<body>
<h1>登陸失敗，賬號密碼找不到或者錯誤</h1>
</body>
</html>

工具類

工具人上線

//登陸使用的方法
Connection conn = null;
  PreparedStatement pst = null;
  ResultSet res = null;
  boolean isQ;
   public boolean Select(String username,String paw)  {
      try {
          conn = JDBC.getConn ( );
          String sql = "SELECT * FROM `username` where `name`=? and `password`=?";
          pst = conn.prepareStatement (sql);
          pst.setObject ( 1,username );
          pst.setObject ( 2,paw );
          res = pst.executeQuery ( );
          if (res.next ()){
              isQ = true;
              System.out.println (res.getObject ( "name" )+" "+res.getObject ( "password" ));
              System.out.println ("登陸成功");
          }else {
              isQ = false;
              System.out.println ("登陸失敗");
          }
      }catch (Exception e){
          e.printStackTrace ();
      }finally {
          JDBC.release ( conn,pst,res );
      }
      return isQ;
  }
  //註冊用的方法
   public void addUser(String name,String paw){
      try {
          conn = JDBC.getConn ( );
          String sql = "insert into `username`(`name`,`password`) values (?,?)";
          pst = conn.prepareStatement ( sql );
          pst.setObject ( 1,name );
          pst.setObject ( 2,paw );
          int i = pst.executeUpdate ( );
          if (i>0){
              System.out.println ("添加成功");
          }
      }catch (Exception e){
          e.printStackTrace ();
      }finally {
          JDBC.release ( conn,pst,res );
      }
  }

登陸的類

package com.li.Servlet.test;

import com.li.Servlet.blit.Way;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class index extends HttpServlet {
  @Override
  protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
      String account = req.getParameter ( "account" );
      String paw = req.getParameter ( "paw" );
      Way way = new Way ();
      if (way.Select ( account,paw )){
          resp.sendRedirect ( "/s4/true.jsp" );
      }else {
          resp.sendRedirect ( "/s4/false.jsp" );
      }
  }

  @Override
  protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
      doGet ( req, resp );
  }
}

註冊的類

package com.li.Servlet.test;

import com.li.Servlet.blit.Way;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class index02 extends HttpServlet {
  @Override
  protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
      String number = req.getParameter ( "number" );
      String word = req.getParameter ( "word" );
       String u = req.getParameter ( "u" );
    if (word.equals ( u )){
          Way way = new Way ( );
          way.addUser ( number,word );
      }else {
          //當兩次密碼不一致的時候瀏覽器響應給用戶當前註冊的頁面
          resp.sendRedirect ( "/s4/Register.jsp" );
      }
  }

  @Override
  protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
      doGet ( req, resp );
  }
}

兩個映射路徑

<!--登陸-->
  <servlet>
      <servlet-name>test</servlet-name>
      <servlet-class>com.li.Servlet.test.index</servlet-class>
  </servlet>
  <servlet-mapping>
      <servlet-name>test</servlet-name>
      <url-pattern>/test</url-pattern>
  </servlet-mapping>
<!--註冊-->
  <servlet>
      <servlet-name>res</servlet-name>
      <servlet-class>com.li.Servlet.test.index02</servlet-class>
  </servlet>
  <servlet-mapping>
      <servlet-name>res</servlet-name>
      <url-pattern>/res</url-pattern>
  </servlet-mapping>

思路

登陸

這個就是用戶輸入的賬號和密碼看看數據庫裡有沒有，有的話就重定向到成功或這失敗的頁面，相當於瀏覽器響應給用戶的請求結果

註冊

相當於就是往數據庫裡面添加一個賬號或者密碼然返回到登陸頁面

這裡我在註冊類面沒有用到重定向，而是在註冊的jsp頁面裡判斷之後跳轉到登陸頁面

註意：這裡為什麼沒在註冊類裡面用重定向

因為使用重定向之後就直接返回瞭登陸類運行的結果

總結

到此這篇關於javaWeb連接數據庫實現簡單登陸註冊功能的文章就介紹到這瞭,更多相關javaWeb登陸註冊功能內容請搜索WalkonNet以前的文章或繼續瀏覽下面的相關文章希望大傢以後多多支持WalkonNet！

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