J2EE Design Pattern - Dispatcher View & Service to Worker

I am trying to understand J2EE design pattern - 'Dispatcher View' & 'Service to Worker'. What is the core idea 开发者_运维百科behind these two approached & how to use these patterns in our application. Can you please explain these two patterns with example?

Thanks for your help.

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The difference it seems to be when the Front Controller invokes the "Service to worker" or the "Dispatcher View" the processing that is done before the invocation is either lightweight or control processing as per http://www.corej2eepatterns.com/CJP2Poster.pdf

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the following is the title of an Apress Book, that will help you to understand more about 'Dispatcher View' & 'Service to Worker' :"Pro Java™ EE Spring Patterns Best Practices and Design Strategies Implementing Java™ EE Patterns with the Spring Framework"