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Service advisor methods are always void methods (this is different from service decorator methods).

The @Match annotation indicates that this advice applies to all services (both your own, and those defined by Tapestry). You will want to narrow down which services are actually targeted in most cases.

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In many cases, the order in which the advice is given is very important; for example, you may want logging first, then transaction management, then security checks. The @Order annotation allows you to explicitly set the order.

Decorators and Advice

Service decorators are another way to achieve the same thing; service advisors are a more recent addition, added in Tapestry 5.1.

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