jdbc 连接mysql数据库_MySQL

jdbc驱动到官网下载，放在jdk的相关目录下面，或者jar文件加入到工程下面

package test_mysql;import java.sql.*;import java.util.Set;public class testjdbc {	public static Connection getConnection() throws ClassNotFoundException, SQLException{		String URL="jdbc:mysql://localhost:3306/employees";		//加载驱动程序		Class.forName("com.mysql.jdbc.Driver");		String user="root";		String passwd="";		//默认密码为空		//还有选择数据库，哪个数据		//DriverManager.		//Connection con=DriverManager.getConnection(URL, user, passwd);		//Connection con=DriverManager.getConnection(url, user, password);		String test_url="";		//String my_url="jdbc:mysql://localhost:3306;DatabaseName=employees;User=root;Password=";		//test_url+=URL+3306+";"+"DatabaseName=employees;"+"User=root;"+"Password="+"";		Connection con=DriverManager.getConnection(URL,user,passwd);		return con;	}	public static void main(String[] args){		String sql="select * fromdepartments";		Statement statement=null;		Connection con=null;		ResultSet set=null;		try {			con = getConnection();			//con.set			if(con==null)				System.out.println("con null");			statement=con.createStatement();			set=statement.executeQuery(sql);			//int n=set.getFetchSize();			//System.out.println(n);			while(set.next()){				System.out.println(set.getString(1)+""+set.getString(2));			}		} catch (ClassNotFoundException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (SQLException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}finally{	if(con!=null)		try {			set.close();			statement.close();			con.close();					} catch (SQLException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		}			}}