Java连接数据库使用JDBC连接器不再需要加载驱动

红太狼 2023-08-17 16:29 116阅读 0赞

> 出错内容：Loading class \`com.mysql.jdbc.Driver'. This is deprecated. The new driver class is \`com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.

下载了mysql-connector-java-8.0.11.jar连接MySQL数据库，加载驱动时发现了一大串红字，显示数据库连接却是成功的。

原因出在这一条语句：

Class.forName("com.mysql.jdbc.Driver");

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MjQwMQ_size_16_color_FFFFFF_t_70][]

异常显示，此驱动自动被注册通过SPI，没有必要再载入驱动类。

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MjQwMQ_size_16_color_FFFFFF_t_70 1][]

看了这个，我把加载驱动的语句去掉试了一下，果然解决了问题。

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MjQwMQ_size_16_color_FFFFFF_t_70 2][]

测试代码：

/**
     * 
     */
    package javatest;
    
    import java.sql.*;
    
    import sun.applet.Main;
    
    /**
     * @author Administrator
     * @数据库封装
     */
    public class JDBCConPackaging {
    		public JDBCConPackaging(){
    			Connection conn;
    			Statement stmt;
    			String user = "root";
    			String pwd = "yuan";
    			try{
    //				Class.forName("com.mysql.jdbc.Driver");
    				conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useSSL=FALSE",user,pwd);
    				stmt = conn.createStatement();
    				System.out.println("连接成功！！！");
    			}catch(Exception e){
    //				e.printStackTrace();
    				System.out.println("连接出错");
    			}
    		}
    		public static void main(String[] args) {
    			new JDBCConPackaging();
    		}
    }

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