java之多态,

package study.java;




abstract class DataAccess




...{


abstract void name();


}




class SqlserverDA extends DataAccess




...{


public void name()




...{


System.out.println("My name is SqlserverDA");


}


}




class OracleDA extends DataAccess




...{


public void name()




...{


System.out.println("My name is OracleDA");


}


}




class FDA




...{


public DataAccess GetDA()




...{


OracleDA myoda=new OracleDA();


return myoda;


}


}






public class MyDataAccess ...{






/** *//**


* @param args


*/




public static void main(String[] args) ...{


DataAccess testDA;


FDA myfda=new FDA();


testDA=myfda.GetDA();


testDA.name();




}




}