import java.sql.*;public class MySQLDBUtil {	PRivate static final String URL = "jdbc:mysql://127.0.0.1:3306/test";	private static final String UNAME = "test";	private static final String PWD = "123456";	private static Connection conn = null;	private static Logger logger = Logger.getLogger(MySqlDBUtil.class);	static {		try {			conn = DriverManager.getConnection(URL, UNAME, PWD);		} catch (Exception e) {			e.printStackTrace();			logger.error(e.toString());		}	}	public static Connection getConnection() throws SQLException {		if (conn == null) {			synchronized (MySqlDBUtil.class) {				if (conn == null) {					conn = DriverManager.getConnection(URL, UNAME, PWD);				}			}		}		return conn;	}}
Maven添加org.mybatis
<dependency>			<groupId>org.mybatis</groupId>			<artifactId>mybatis</artifactId>			<version>3.4.0</version>		</dependency>