java找不到适合jdbc的驱动程序？

Question

我从Oracle的网站上获取了这个示例，但我无法实现它。它不断地显示错误。我已经将mysql 5.1驱动程序jar添加到我的项目库文件夹中 以及我的构建路径。如何修复代码

链接-http://docs.oracle.com/javase/tutorial/jdbc/basics/connecting.html

错误-

java.sql.SQLException: No suitable driver found for jdbc:JavaEE://localHost:3306/
    at java.sql.DriverManager.getConnection(DriverManager.java:602)
    at java.sql.DriverManager.getConnection(DriverManager.java:154)
    at com.beans.us.dao.Data.getConnection(Data.java:25)
    at com.beans.us.dao.Data.main(Data.java:43)
Cannot connect to database

代码-

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;

public class Data {

    public static Connection getConnection() {

        Connection conn = null;
        Properties connectionProps = new Properties();
        String userName = "root";
        String password = "root";
        String dbms = "JavaEE";
        String serverName = "localHost";
        String portNumber = "3306";

        connectionProps.put("user", userName);
        connectionProps.put("password", password);

        try {

            conn = DriverManager.getConnection("jdbc:" + dbms + "://"
                    + serverName + ":" + portNumber + "/", connectionProps);
        } catch (SQLException sQLException) {
            sQLException.printStackTrace();
        }

        if (conn != null) {
            System.out.println("Connected to database");
        } else {
            System.out.println("Cannot connect to database");
        }

        return conn;
    }

    public static void main(String[] args) {

        getConnection();

    }

}

Answer 1

您的连接字符串是：

"jdbc:JavaEE://..."

但MySQL应该是这样的

"jdbc:mysql://..."

此外，您忘记加载驱动程序：

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

需要在打电话之前完成

conn = DriverManager.getConnection(...);

Answer 2

您的jdbc字符串格式不正确，请查看以下问题的答案：

What is the MySQL JDBC driver connection string?

Answer 3

你好像忘了给司机装东西了

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

Class.forName()使类加载器将类加载到内存中。JDBC驱动程序类包含一个静态初始值设定项块，它将驱动程序注册到DriverManager以供以后参考

之前没有注意到这一点，您的连接字符串应该是"jdbc:mysql://localhost:3306/dbname"