jdbc连接数据库

private String dburl = "jdbc:mysql://localhost:3306/db_library";    private String dbuserName = "root";    private String dbpassword = "123456";    private String jdbcName = "com.mysql.jdbc.Driver";        public   Connection getcon() throws ClassNotFoundException, SQLException{        Class.forName(jdbcName);        Connection con=DriverManager.getConnection(dburl,dbuserName,dbpassword);               return con;    }    public void closeCon(Connection con) throws SQLException{        if(con!=null){            con.close();        }    }

dburl的最后一定要换成自己的数据库名，否则其他的语句都得不到执行

一个con用完之后记得调用closecon