sinewmy 's Profile

The Model 2 architecture uses a Java servlet to receive the HTTP requests from the browser and to communicate with the model layer. The JSPs are used only for presentation. The same controller that receives the request is responsible for determining which view gets returned back to the client.

However, please note that the Spring Framework's transaction infrastructure
code will, by default, only mark a transaction for rollback in
the case of runtime, unchecked exceptions; that is, when the thrown exception is an
instance or subclass of RuntimeException.
(Errors will also - by default - result in a rollback.) Checked
exceptions that are thrown from a transactional method will
not result in the transaction being rolled back.

Pointcut: A predicate that matches join points.
Advice is associated with a pointcut expression and runs at any join
point matched by the pointcut

Pointcuts enable advice to be targeted independently of the Object-Oriented hierarchy.
For example, an around advice providing declarative transaction management can
be applied to a set of methods spanning multiple objects (such as all business
operations in the service layer).

Aspects (classes annotated with @Aspect) may have
methods and fields just like any other class. They may also contain pointcut, advice,
and introduction (inter-type) declarations.

A pointcut declaration has two parts: a
signature comprising a name and any parameters, and a pointcut expression
that determines exactly which method executions we are interested in.

Sometimes you need access in the advice body to the actual value that was returned. You
can use the form of @AfterReturning that binds the return
value for this:

The XML style has two disadvantages. Firstly it does not fully encapsulate
the implementation of the requirement it addresses in a single place.
The DRY principle says that there should be a single, unambiguous, authoritative
representation of any piece of knowledge within a system. When using the
XML style, the knowledge of how a requirement is implemented is split across
the declaration of the backing bean class, and the XML in the configuration
file. When using the @AspectJ style there is a single module - the aspect - in
which this information is encapsulated. Secondly, the XML style is more
limited in what in can express than the @AspectJ style: only the "singleton"
aspect instantiation model is supported, and it is not possible to combine
named pointcuts declared in XML. For example, in the @AspectJ style we
can write something like:

@AspectJ aspects can be
understood both by Spring AOP and by AspectJ - so if you later decide
you need the capabilities of AspectJ to implement additional requirements
then it is very easy to migrate to an AspectJ based approach.