Spring MVC provides a convenient way to add your custom mapping handler, view resolver,locale resolution,theme resolution and request handlers. This convenience is achieved by strategy pattern. This feature makes Spring MVC different from other web framework because it is not request-oriented and driven web framework.
In the package of Spring MVC, one file named DispatcherServlet.properties is included in the jar packages. In that property file, all kinds of default implementations are defined. In the normal process of Spring MVC, it usually loads your custom implementations at first. If your custom ones are not found, it will turn to DispatcherServlet.properties for help. That is to say, all of the default implementations are the last resorts.
org.springframework.web.servlet.LocaleResolver=org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver org.springframework.web.servlet.ThemeResolver=org.springframework.web.servlet.theme.FixedThemeResolver org.springframework.web.servlet.HandlerMapping=org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping,\ org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping org.springframework.web.servlet.HandlerAdapter=org.springframework.web.servlet.mvc.HttpRequestHandlerAdapter,\ org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter,\ org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter org.springframework.web.servlet.HandlerExceptionResolver=org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerExceptionResolver,\ org.springframework.web.servlet.mvc.annotation.ResponseStatusExceptionResolver,\ org.springframework.web.servlet.mvc.support.DefaultHandlerExceptionResolver org.springframework.web.servlet.RequestToViewNameTranslator=org.springframework.web.servlet.view.DefaultRequestToViewNameTranslator org.springframework.web.servlet.ViewResolver=org.springframework.web.servlet.view.InternalResourceViewResolver org.springframework.web.servlet.FlashMapManager=org.springframework.web.servlet.support.SessionFlashMapManager