Darshan-
  The concept of static methods remain same whether it is a web
application or java standalone application. As u might be knowing if u
write a static method ur sharing the same method for mulitple calls.
So if u sharing any kind of resources using static will be a problem
and I feel using static (not always) is not a good design approach

-Rajeev
SCEA


On Tue, 23 Nov 2004 00:10:09 -0700, Darshan <dkumar@(protected):
> Hi T.
>
> May be :)
>
> Not using any frameworks.
>
> There is one post at theserverside.com forum(thread #14864) , which tells
> that as long as you pass the connection object from the caller as a param
> to the static method in DAO and the DAO is not using any other class level
> variables, it should be fine. (?)
>
>  Clarification on this is much appreciated.
>
> Thanks
> Darshan
>
>
>
> On Mon, 22 Nov 2004 22:53:58 -0600, Tareq <tayub@(protected):
>
> >Your PM may need to be educated on software patterns and architecture.
> >
> >The DAO pattern encapsulates data access to a data source. First, your
> >design should be interface driven which would mandate using concrete
> >classes. Second, having a DAO implementation can assist in varying
> >implementations. Third, Testability - I am assuming you do unit testing
> >and to facilitate unit test components dependent on the DAO layer you
> >would need mock objects (eg. Look at Spring's use of dependency
> >injection)
> >
> >T.
> >
> >-----Original Message-----
> >From: An interest list for Sun Java Center J2EE Pattern Catalog
> >[mailto:J2EEPATTERNS-INTEREST@(protected)
> >Sent: Monday, November 22, 2004 10:35 PM
> >To: J2EEPATTERNS-INTEREST@(protected)
> >Subject: Re: DAO pattern
> >
> >Hi Ananthalakshmi,
> >
> >  Thanks for the code explanation and the same to group members. One
> >more
> >small question. My PM suggesting me to use static methods in DAO class.
> >what is the difference (In the design perspective) by putting the DAO's
> >methods as static and non-static? Is there any impact if we keep the
>
>
> >methods as static in a web application?
> >
> >Regards
> >Darshan
> >
> >On Sun, 21 Nov 2004 06:54:53 -0700, Ananthalakshmi Subramaniyam
> ><ananthalakshmi_mca@(protected):
> >
> >>On Thu, 18 Nov 2004 23:11:06 -0700, Darshan Kashi
> ><dkumar@(protected)>
> >>wrote:
> >>
> >>>Hi,
> >>>
> >>> Thanks for your reply. I just gone through the link you provided, and
> >its
> >>>really useful for me. There is one point i need some clarification.
> >>>
> >>>In that article the author mentioned two approaches
> >>>
> >>>1. Transaction demarcation using JDBC
> >>>     (The <B>caller has no way to demarcate</B> the transaction)
> >>>2. Transaction demarcation using JTA
> >>>     (The <B>caller is responsible for demarcating</B> the
> >transaction)
> >>>
> >>>I need to control the trasaction from the caller(not in DAO), and at
> >the
> >>>same time i don't want to go for JTA. Is it not possible?
> >>>
> >>>Regards
> >>>Darshan
> >>>
> >>>
> >>>On Thu, 18 Nov 2004 09:24:35 -0300, German M. Gomez
> >>><german_m_gomez@(protected):
> >>>
> >>>>I believe you will find this link useful http://www-
> >>>106.ibm.com/developerworks/java/library/j-dao/
> >>>>
> >>>>See Transaction demarcation
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>___________________________________
> >>>>?Llevate a Yahoo! en tu Unifó®¡ >>Ahora podé³ usar Yahoo! Messenger
> >en tu
> >>Unifó®¬ en cualquier momento y
> >>>lugar.
> >>>>Encontrá ­á³ informació® ¥n: http://ar.mobile.yahoo.com/sms.html
> >>>>
> >>>>====================================================================
> >>>>Companion Site: http://www.corej2eepatterns.com
> >>>>J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns
> >>>>List Archive: http://archives.java.sun.com/archives/j2eepatterns-
> >>>interest.html
> >>>>Unsubscribing: email "signoff J2EEPATTERNS-INTEREST" to
> >>>listserv@(protected)
> >>>
> >>>====================================================================
> >>>Companion Site: http://www.corej2eepatterns.com
> >>>J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns
> >>>List Archive: http://archives.java.sun.com/archives/j2eepatterns-
> >>interest.html
> >>>Unsubscribing: email "signoff J2EEPATTERNS-INTEREST" to
> >>listserv@(protected)
> >>
> >>Hi,
> >>
> >>Normally, it is best practice to handle Transaction demarcation outside
> >of
> >>DAO, in order to demarcate Transaction between multiple DAOs. This
> >approach
> >>is more flexible.
> >>
> >>For example,
> >>
> >>public class UserTransaction {
> >>  Connection conn = null;
> >>  String strUser = null;
> >>  String strDbUrl = null;
> >>  String strDbUser = null;
> >>  String strPassword = null;
> >>
> >>  public UserTransaction(String strURL, String strUser,
> >>                 String strPassword) {
> >>   this.strDbUrl = strURL;
> >>   this.strDbUser = strUser;
> >>   this.strPassword = strPassword;
> >>  }
> >>  public void beginTransaction(...) {}
> >>  public void endTransaction(...) {}
> >>  public Connection getConnection() {return connection;}
> >>  public void commit() {}
> >>  public void rollback() {}
> >>}
> >>public class MyDAOFactory {
> >>  public static UserTransaction transaction = null;
> >>  public static final String DRIVER=
> >>   "COM.cloudscape.core.RmiJdbcDriver";
> >>  public static final String DBURL=
> >>   "jdbc:cloudscape:rmi://localhost:1099/CoreJ2EEDB";
> >>  public static final String USER ="user";
> >>  public static final String PASSWORD = "pwd";
> >>
> >>  public static UserTransaction getUserTransaction() {
> >>   if(transaction == null ) {
> >>     UserTransaction transaction = new UserTransaction
> >>(DRIVER,DBRUL,USER,PASSWORD);
> >>   }
> >>   return transaction;
> >>  }
> >>  ...
> >>  public AccountDAO getAccountDAO();
> >>}
> >>public class AccountDAO {
> >>  public void credit() {
> >>   UserTransaction transaction =
> >>     MyDAOFactory.getUserTransaction();/use existing user transaction
> >or
> >>                            create new one.
> >>   Connection connection = transaction.getConnection();
> >>   Statement stmt = connection.createStatement(sqlQuery);
> >>   //do the operations.
> >>  }
> >>  public void debit() {}
> >>  ...
> >>}
> >>
> >>In Caller class,
> >>
> >>MyDAOFactory daoFactory = new MyDAOFactory();
> >>UserTransaction transaction = MyDAOFactory.getUserTransaction();
> >>transaction.beginTransaction();
> >>AccountDAO accountDAO = daoFactory.getAccountDAO();
> >>try {
> >>accountDAO.credit();
> >>accountDAO.debit();
> >>...
> >>transaction.commit();
> >>} catch(myDAOException ex) {
> >> transaction.rollback();
> >>}
> >>transaction.endTransaction();
> >>
> >>The above approach is helpful in both DAO demarcated Transaction and
> >>caller demarcated transaction. ie, in DAO demarcated methods, you may
> >have
> >>the following implementation,
> >>
> >>public void autonomousCredit() {
> >>   UserTransaction transaction =
> >>     MyDAOFactory.getUserTransaction();/use existing user transaction
> >or
> >>                            create new one.
> >>   transaction.beginTransaction();
> >>   Connection connection = transaction.getConnection();
> >>   Statement stmt = connection.createStatement(sqlQuery);
> >>   try {
> >>    //do the operations.
> >>    transaction.commit();
> >>   } catch(Exception ex) {
> >>    transaction.rollback();
> >>   }
> >>   transaction.endTransaction();
> >>}
> >>
> >>Thanks,
> >>H.Ananthalakshmi.Hi,
> >>
> >>Normally, it is best practice to handle Transaction demarcation outside
> >of
> >>DAO, in order to demarcate Transaction between multiple DAOs. This
> >approach
> >>is more flexible.
> >>
> >>For example,
> >>
> >>public class UserTransaction {
> >>  Connection conn = null;
> >>  String strUser = null;
> >>  String strDbUrl = null;
> >>  String strDbUser = null;
> >>  String strPassword = null;
> >>
> >>  public UserTransaction(String strURL, String strUser,
> >>                 String strPassword) {
> >>   this.strDbUrl = strURL;
> >>   this.strDbUser = strUser;
> >>   this.strPassword = strPassword;
> >>  }
> >>  public void beginTransaction(...) {}
> >>  public void endTransaction(...) {}
> >>  public Connection getConnection() {return connection;}
> >>  public void commit() {}
> >>  public void rollback() {}
> >>}
> >>public class MyDAOFactory {
> >>  public static UserTransaction transaction = null;
> >>  public static final String DRIVER=
> >>   "COM.cloudscape.core.RmiJdbcDriver";
> >>  public static final String DBURL=
> >>   "jdbc:cloudscape:rmi://localhost:1099/CoreJ2EEDB";
> >>  public static final String USER ="user";
> >>  public static final String PASSWORD = "pwd";
> >>
> >>  public static UserTransaction getUserTransaction() {
> >>   if(transaction == null ) {
> >>     UserTransaction transaction = new UserTransaction
> >>(DRIVER,DBRUL,USER,PASSWORD);
> >>   }
> >>   return transaction;
> >>  }
> >>  ...
> >>  public AccountDAO getAccountDAO();
> >>}
> >>public class AccountDAO {
> >>  public void credit() {
> >>   UserTransaction transaction =
> >>     MyDAOFactory.getUserTransaction();/use existing user transaction
> >or
> >>                            create new one.
> >>   Connection connection = transaction.getConnection();
> >>   Statement stmt = connection.createStatement(sqlQuery);
> >>   //do the operations.
> >>  }
> >>  public void debit() {}
> >>  ...
> >>}
> >>
> >>In Caller class,
> >>
> >>MyDAOFactory daoFactory = new MyDAOFactory();
> >>UserTransaction transaction = MyDAOFactory.getUserTransaction();
> >>transaction.beginTransaction();
> >>AccountDAO accountDAO = daoFactory.getAccountDAO();
> >>try {
> >>accountDAO.credit();
> >>accountDAO.debit();
> >>...
> >>transaction.commit();
> >>} catch(myDAOException ex) {
> >> transaction.rollback();
> >>}
> >>transaction.endTransaction();
> >>
> >>The above approach is helpful in both DAO demarcated Transaction and
> >>caller demarcated transaction. ie, in DAO demarcated methods, you may
> >have
> >>the following implementation,
> >>
> >>public void autonomousCredit() {
> >>   UserTransaction transaction =
> >>     MyDAOFactory.getUserTransaction();/use existing user transaction
> >or
> >>                            create new one.
> >>   transaction.beginTransaction();
> >>   Connection connection = transaction.getConnection();
> >>   Statement stmt = connection.createStatement(sqlQuery);
> >>   try {
> >>    //do the operations.
> >>    transaction.commit();
> >>   } catch(Exception ex) {
> >>    transaction.rollback();
> >>   }
> >>   transaction.endTransaction();
> >>}
> >>
> >>Thanks,
> >>H.Ananthalakshmi.
> >>
> >>====================================================================
> >>Companion Site: http://www.corej2eepatterns.com
> >>J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns
> >>List Archive: http://archives.java.sun.com/archives/j2eepatterns-
> >interest.html
> >>Unsubscribing: email "signoff J2EEPATTERNS-INTEREST" to
> >listserv@(protected)
> >
> >====================================================================
> >Companion Site: http://www.corej2eepatterns.com
> >J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns
> >List Archive:
> >http://archives.java.sun.com/archives/j2eepatterns-interest.html
> >Unsubscribing: email "signoff J2EEPATTERNS-INTEREST" to
> >listserv@(protected)
> >
> >====================================================================
> >Companion Site: http://www.corej2eepatterns.com
> >J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns
> >List Archive: http://archives.java.sun.com/archives/j2eepatterns-
> interest.html
> >Unsubscribing: email "signoff J2EEPATTERNS-INTEREST" to
> listserv@(protected)
>
> ====================================================================
> Companion Site: http://www.corej2eepatterns.com
> J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns
> List Archive: http://archives.java.sun.com/archives/j2eepatterns-interest.html
> Unsubscribing: email "signoff J2EEPATTERNS-INTEREST" to listserv@(protected)
>


--
*****************************
Ranjeeth kumar,
SCEA
*************************************

====================================================================
Companion Site: http://www.corej2eepatterns.com
J2EE BluePrints: http://java.sun.com/blueprints/corej2eepatterns
List Archive: http://archives.java.sun.com/archives/j2eepatterns-interest.html
Unsubscribing: email "signoff J2EEPATTERNS-INTEREST" to listserv@(protected)