jdbc报java.lang.ClassNotFoundException: com.mysql.jdbc.Drive

Posted 2020-10-24 Visitors

　　今天从开始写了一个jdbc连接mysql驱动的程序

　　真的是各种报错啊

首先这是代码

package com.dmeck;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class Jdbcbase {

	public static void main(String[] args) {
		String url = "jdbc:mysql://localhost:3306/mytest";
		String user="root";
		String pass="mysql" ;
		String className="com.mysql.jdbc.Driver";
		try{
			Class.forName(className);
		}catch(Exception e) {
            System.out.print("Error loading Mysql Driver!");
            e.printStackTrace();
		}
		Connection connection;
		try {
			
			connection = DriverManager.getConnection(url, user, pass);
			Statement createStatement = connection.createStatement();

			ResultSet query = createStatement.executeQuery("select * from user");
			while(query.next()) {
				System.out.println(query.getString("user"));
			}
			connection.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
	}
}

　　嗯，先说下问题

项目运行时会出现

Error loading Mysql Driver!java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:264)
    at com.dmeck.Jdbcbase.main(Jdbcbase.java:17)
java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/mytest
    at java.sql.DriverManager.getConnection(DriverManager.java:689)
    at java.sql.DriverManager.getConnection(DriverManager.java:247)
    at com.dmeck.Jdbcbase.main(Jdbcbase.java:25)

首先这个错误我无法复现，因为我的项目是maven管理的

　　　　jdbc驱动是5.1.6

　　这个错误是因为maven网络不好而引起的jar包出现错误，只要eclispe加载jar的字节文件不是下列现象就说明你的jar包有问题