Use of Helper classes

[Mohankumar G]

Can any one help me in explaining the need of helper classes and where we can use it?

[Pradeep bhatt]

You mean Helper classes for EJB?

[Mohankumar G]

Yes. for EJB

[Vishwa Kumba]

One example that I have come across is :
Order and OrderlineItems. These need not be 2 different Entity Beans.
The design could have only 1 EJB, the OrderEJB containing a Collection of
OrderlineItems, which are just simple java classes, called as Helper Classes. Orders and OrderlineItems are still stored in different tables.

[Pradeep bhatt]

You could have a helper class for sending confirmation emails to Customers.

[Sivasundaram Umapathy]

Helper classes can be used as dependent objects(OrderlineItems of vishkumar) or may be as Value Object POJO's or as Utility classes (like email sender of pradeep).