What is need of DAO? Write one simple DAO example?
Answer Posted / naveen kumar v
DAO: Data Access Object. here the main concept of DAO is to
communicate with the database. DAO mainly contains
1.) DAOFactory: this specifies which kind of database
(wether MySQL or ORACLE or MSSQL etc...).
2.) SQLFactory: which extends the DAOFactory. Here we do
all the connection stuffs.deciding te driver, hostname,
URL, username, password etc and also getting the Connection
object.
3.) AdminDAO: this is a interface where we declare all the
methods which we need in our application to perform all the
database related operation.
4.) SQLAdminFactory: this implements the AdminDAO
interface, all its method. this also gets the connection
from SQLFactory.
5.) TransactionControlDAO: here we keep the commit and
roolback methods.
if required...
6) ConnectionConstant: in this file we can mention the file
name (.properties file) where we keep the connection
detals, like hostname, username, password, etc...
Is This Answer Correct ? | 14 Yes | 4 No |
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