| Q: |
What
are transaction attributes?
|
| A: |
The
transaction attribute specifies how the
Container must manage transactions for
a method when a client invokes the method
via the enterprise bean’s home or component
interface or when the method is invoked
as the result of the arrival of a JMS
message. (Sun's EJB Specification) Below
is a list of transactional attributes:
1. NotSupported - transaction
context is unspecified.
2. Required - bean's
method invocation is made within a transactional
context. If a client is not associated
with a transaction, a new transaction
is invoked automatically.
3. Supports - if a transactional
context exists, a Container acts like
the transaction attribute is Required,
else - like NotSupported.
4. RequiresNew - a method
is invoked in a new transaction context.
5. Mandatory - if a transactional
context exists, a Container acts like
the transaction attribute is Required,
else it throws a javax.ejb.TransactionRequiredException.
6. Never - a method executes
only if no transaction context is specified.
|
| |
|
|