org.springframework.web.servlet.mvc.multiaction (Spring Framework 3.2.1.RELEASE API)
Date: 2013-01-24

# Package org.springframework.web.servlet.mvc.multiaction

Package allowing MVC Controller implementations to handle requests at method rather than class level.

See: Description

- Interface Summary
  Interface | Description
  --- | ---
  MethodNameResolver | Interface that parameterizes the MultiActionController class using the Strategy GoF Design pattern, allowing the mapping from incoming request to handler method name to be varied without affecting other application code.

- Class Summary
  Class | Description
  --- | ---
  AbstractUrlMethodNameResolver | Abstract base class for URL-based `MethodNameResolver` implementations.
  InternalPathMethodNameResolver | Simple implementation of `MethodNameResolver` that maps URL to method name.
  MultiActionController | `Controller` implementation that allows multiple request types to be handled by the same class.
  ParameterMethodNameResolver | Implementation of `MethodNameResolver` which supports several strategies for mapping parameter values to the names of methods to invoke.
  PropertiesMethodNameResolver | The most flexible out-of-the-box implementation of the `MethodNameResolver` interface.

- Exception Summary
  Exception | Description
  --- | ---
  NoSuchRequestHandlingMethodException | Exception thrown when there is no handler method ("action" method) for a specific HTTP request.

## Package org.springframework.web.servlet.mvc.multiaction Description

Package allowing MVC Controller implementations to handle requests at method rather than class level. This is useful when we want to avoid having many trivial controller classes, as can easily happen when using an MVC framework.

Typically a controller that handles multiple request types will extend MultiActionController, and implement multiple request handling methods that will be invoked by reflection if they follow this class' naming convention. Classes are analyzed at startup and methods cached, so the performance overhead of reflection in this approach is negligible.

This approach is analogous to the Struts 1.1 DispatcherAction class, but more sophisticated, as it supports configurable mapping from requests to URLs and allows for delegation as well as subclassing.

This package is discussed in Chapter 12 of Expert One-On-One J2EE Design and Development by Rod Johnson, and used in the sample application.