@Stateless
public static class MyBean implements MyBusinessInterface {
@TransactionAttribute(TransactionAttributeType.MANDATORY)
public String codeRed(String s) {
return s;
}
public String codeBlue(String s) {
return s;
}
}Transaction Annotations
Also see Testing Transactions for an example of how to use and test EJB transaction attributes
The javax.ejb.TransactionAttribute annotation (@TransactionAttribute)
can be applied to a bean class or it’s methods.
Usage of the @TransactionAttribute requires you to specify one of six
different transaction attribute types defined via the
javax.ejb.TransactionAttributeType enum.
-
TransactionAttributeType.MANDATORY
-
TransactionAttributeType.REQUIRED
-
TransactionAttributeType.REQUIRES_NEW
-
TransactionAttributeType.SUPPORTS
-
TransactionAttributeType.NOT_SUPPORTED
-
TransactionAttributeType.NEVER
Per EJB 3.0 the default transaction attribute for all EJB 3.0 applications is REQUIRED. The default transaction attribute for EJB 2.1, 2.0 and 1.1 applications is vendor specific. In OpenEJB EJB 2.1, 2.0 and 1.1 applications also use REQUIRED as the default.
Attribute Types summary
A simplistic way to visualize the transaction attributes is as follows.
Failing
Correcting
No Change
Transacted
MANDATORY
REQUIRED, REQUIRES_NEW
SUPPORTS
Not Transacted
NEVER
NOT_SUPPORTED
SUPPORTS
The "Transacted" and "Not Transacted" categories represent the container guarantee, i.e. if the bean method will or will not be invoked in a transaction. The "Failing", "Correcting", and "No Change" categories represent the action take by the container to achieve that guarantee.
For example, Never and Mandatory are categorized as "Failing" and will cause the container to throw an exception to the caller if there is (Tx Never) or is not (Tx Mandatory) a transaction in progress when the method is called. The attributes Required, RequiresNew, and NotSupported are categorized as "Correcting" as they will cause the container to adjust the transactional state automatically as needed to match the desired state, rather than blocking the invocation by throwing an exception.
Detailed description of each Attribute
MANDATORY
A MANDATORY method is guaranteed to always be executed in a transaction. However, it’s the caller’s job to take care of suppling the transaction. If the caller attempts to invoke the method outside of a transaction, then the container will block the call and throw them an exception.
REQUIRED
A REQUIRED method is guaranteed to always be executed in a transaction. If the caller attempts to invoke the method outside of a transaction, the container will start a transaction, execute the method, then commit the transaction.
REQUIRES_NEW
A REQUIRES_NEW method is guaranteed to always be executed in a transaction. If the caller attempts to invoke the method inside or outside of a transaction, the container will still start a transaction, execute the method, then commit the transaction. Any transaction the caller may have in progress will be suspended before the method execution then resumed afterward.
NEVER
A NEVER method is guaranteed to never be executed in a transaction. However, it’s the caller’s job to ensure there is no transaction. If the caller attempts to invoke the method inside of a transaction, then the container will block the call and throw them an exception.
NOT_SUPPORTED
A NOT_SUPPORTED method is guaranteed to never be executed in a transaction. If the caller attempts to invoke the method inside of a transaction, the container will suspend the caller’s transaction, execute the method, then resume the caller’s transaction.
SUPPORTS
A SUPPORTS method is guaranteed to adopt the exact transactional state of the caller. These methods can be invoked by caller’s inside or outside of a transaction. The container will do nothing to change that state.
On Methods
-
codeRed will be invoked with the attribute of MANDATORY
-
codeBlue will be invoked with the default attribute of REQUIRED
On Classes
@Stateless
@TransactionAttribute(TransactionAttributeType.MANDATORY)
public static class MyBean implements MyBusinessInterface {
public String codeRed(String s) {
return s;
}
public String codeBlue(String s) {
return s;
}
}-
codeRed and codeBlue will be invoked with the attribute of MANDATORY
Mixed on classes and methods
@Stateless
@TransactionAttribute(TransactionAttributeType.SUPPORTS)
public static class MyBean implements MyBusinessInterface {
@TransactionAttribute(TransactionAttributeType.NEVER)
public String codeRed(String s) {
return s;
}
public String codeBlue(String s) {
return s;
}
@TransactionAttribute(TransactionAttributeType.REQUIRED)
public String codeGreen(String s) {
return s;
}
}-
codeRed will be invoked with the attribute of NEVER
-
codeBlue will be invoked with the attribute of SUPPORTS
-
codeGreen will be invoked with the attribute of REQUIRED
Illegal Usage
Generally, transaction annotationss cannot be made on AroundInvoke methods and most callbacks.
The following usages of @TransactionAttribute have no effect.
@Stateful
public class MyStatefulBean implements MyBusinessInterface {
@PostConstruct
@TransactionAttribute(TransactionAttributeType.NEVER)
public void constructed(){
}
@PreDestroy
@TransactionAttribute(TransactionAttributeType.NEVER)
public void destroy(){
}
@AroundInvoke
@TransactionAttribute(TransactionAttributeType.NEVER)
public Object invoke(InvocationContext invocationContext) throws Exception {
return invocationContext.proceed();
}
@PostActivate
@TransactionAttribute(TransactionAttributeType.NEVER)
public void activated(){
}
@PrePassivate
@TransactionAttribute(TransactionAttributeType.NEVER)
public void passivate(){
}
}