Accessing a static resouces in a web app.

[sean]

Hi,

I have a struts application that creates a DAO factory on application initialisation.

The DAO factory is initialised with a DataSource instance like this

Code:

private IDAOFactory getDaoFactory() throws InitialisationError
{
	logger.debug(IConstants.ENTERING);

	IDAOFactory daoFactory = null;
		
	if(IConstants.JDBC_DAO_FACTORY.equals(getDaoFactoryType()))
	{
		daoFactory = new JDBCDaoFactory(getDataSource());
	}
		
	logger.debug(IConstants.EXITING);
	return daoFactory;
}

Once the DAO factory is retrieved it is passed to a DAOHelper class like this

Code:

DAOHelper.setDaoFactory(getDaoFactory());

The DAOHelper class has two methods:

Code:

public static IDAOFactory getDaoFactory()
{
	return daoFactory;
}

public static void setDaoFactory(IDAOFactory daoFactory)
{
	DAOHelper.daoFactory = daoFactory;
}

This now enables any class intance to get the DAO factory. What I want to know is - is this safe. If two threads call

Code:

DAOHelper.getDaoFactory()

at the same time what will happen? Should I synchronize the

Code:

DAOHelper.getDaoFactory()

mathod?

Thanks.

[goldhouse]

I would recomment to make the DaoFactory a singleton instance and bind it So every time you will check if there is already check for existing one if not present return a new one, I think that way you can avoid synchornization

[sean]

Thanks for your reply. Can you tell me what you mean by 'bind it'?

Thanks again.

[goldhouse]

Two choices one to make it public static ,
second a better one JVM_Bind , the same way we used to bind it with datasource connections , If you dont know go with the statc thing