intelli IDEA servlet jsp connect mysql 8.0 java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver solution

The connection mode has changed after mysql8.0, so it needs to be set to

com.mysql.cj.jdbc.Driver

Choose the best version according to your own mysql  https://dev.mysql.com/downloads/connector/j/  , my here is mysql 8.0.25

1 code

import java.io.IOException;import java.io.PrintWriter;import java.sql.*; import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse; /** * Servlet implementation class DatabaseAccess */@WebServlet("/DatabaseAccess")public class DatabaseAccess extends HttpServlet {    private static final long serialVersionUID = 1L;    // JDBC 驱动名及数据库 URL    static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";    static final String DB_URL = "jdbc:mysql://localhost:3306/RUNOOB?useSSL=true&characterEncoding=utf-8&serverTimezone=GMT";     // 数据库的用户名与密码,需要根据自己的设置    static final String USER = "root";    static final String PASS = "aA0kirito";    /**     * @see HttpServlet#HttpServlet()     */    public DatabaseAccess() {        super();        // TODO Auto-generated constructor stub    }     /**     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)     */    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {        Connection conn = null;        Statement stmt = null;        // 设置响应内容类型        response.setContentType("text/html;charset=UTF-8");        PrintWriter out = response.getWriter();        String title = "Servlet Mysql 测试 - 菜鸟教程";        String docType = "<!DOCTYPE html>\n";        out.println(docType +                "<html>\n" +                "<head><title>" + title + "</title></head>\n" +                "<body bgcolor=\"#f0f0f0\">\n" +                "<h1 align=\"center\">" + title + "</h1>\n");        try{            // 注册 JDBC 驱动器            Class.forName(JDBC_DRIVER);             // 打开一个连接            conn = DriverManager.getConnection(DB_URL,USER,PASS);             // 执行 SQL 查询            stmt = conn.createStatement();            String sql;            sql = "SELECT id, name, url FROM websites";            ResultSet rs = stmt.executeQuery(sql);             // 展开结果集数据库            while(rs.next()){                // 通过字段检索                int id  = rs.getInt("id");                String name = rs.getString("name");                String url = rs.getString("url");                 // 输出数据                out.println("ID: " + id);                out.println(", 站点名称: " + name);                out.println(", 站点 URL: " + url);                out.println("<br />");            }            out.println("</body></html>");             // 完成后关闭            rs.close();            stmt.close();            conn.close();        } catch(SQLException se) {            // 处理 JDBC 错误            se.printStackTrace();        } catch(Exception e) {            // 处理 Class.forName 错误            e.printStackTrace();        }finally{            // 最后是用于关闭资源的块            try{                if(stmt!=null)                    stmt.close();            }catch(SQLException se2){            }            try{                if(conn!=null)                    conn.close();            }catch(SQLException se){                se.printStackTrace();            }        }     }     /**     * @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);    }}

2 Set up JDBC

Then how to import to the engineering problem, there are a lot of pits here, the following methods are not working

All prompt java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver, this must be the path is not set, and the modules /libraries/sdks setting will not work

Best I found that it is enough to place the jdbc jar in WEB-INF