Here are some transaction attributes
Required : No new transaction is created when the required attributed is linked to the transaction.
Requires New : There is always present the addition of a new transaction when this attributed is linked to the transaction.
Not Supported : If the method is linked to this attribute then the method does not remain part of the transaction
Supported : It acts in the conditional case that depends on the calling component. If the calling element is linked with transaction then the method act as a required attribute. If the calling component is not linked with the transaction then the method acts as NOT SUPPORTED.
Mandatory : The method is always called from the calling element transaction context when the method is linked to this attribute.
Never : The method is never called from the calling element transaction context when the method is linked to this attribute.
Support is the default transaction value of EJB.
