Re: [Springframework-developer] new bean factory and application context features

[Rod J. <rod...@in...>]

> What I'm most excited about is the BeanPostProcessor hook. I expect that
to be very powerful, as already indicated by the respective test case in
StaticApplicationContextSuite. Another example that I've prototyped is the
following (not yet in CVS):
> public class AutoProxyCreator implements BeanPostProcessor {
>   private List beanNames;
>   private Interceptor[] interceptors;
>
>   public void setBeanNames(String[] beanNames) {
>     this.beanNames = Arrays.asList(beanNames);
>   }
>
>   public void setInterceptors(Interceptor[] interceptors) {
>     this.interceptors = interceptors;
>   }
>
>   public Object postProcessBean(Object bean, String name,
RootBeanDefinition definition) {
>     if (this.beanNames != null && this.beanNames.contains(name)) {
>       ProxyFactory proxyFactory = new ProxyFactory();
>       for (int i = 0; i < this.interceptors.length; i++) {
>         proxyFactory.addInterceptor(this.interceptors[i]);
>       }
>       proxyFactory.addInterceptor(new InvokerInterceptor(bean));
>       return proxyFactory.getProxy();
>     }
>     else {
>       return bean;
>     }
>   }
> }
> Of course, source-level metadata would allow for just 1 BeanPostProcessor
plus the 10 target beans (11 beans in total), with the transaction
attributes being kept with the respective methods in the source code. This
would just get rid of 1 bean but of a pretty bloated one: the
TransactionInterceptor definition with its centralized transaction
attributes for the whole app.

This _is_ exciting.

Source-level metadata might also mean we wouldn't need to know the names of
the transactional beans. We sould simply need to install a BeanPostProcessor
that would look up metadata. It could work with arbitrary attributes,
depending on registered "attribute scanners".

Combined with good metadata support, I think we can match the ease of use of
.NET for enterprise services in M3. I have always seen this as the killer
application for Spring AOP.

Regards,
Rod