常用数据库连接

       DB2:

　　driverClassName:com.ibm.db2.jcc.DB2Driver

　　url:jdbc:db2://localhost:50000/sample

　　Oracle:

　　driverClassName:oracle.jdbc.driver.OracleDriver

　　url:jdbc:oracle:thin:@localhost:1521:orcl

　　MySql:

　　driverClassName:com.mysql.jdbc.Driver

　　url:jdbc:mysql://localhost:3306/test