org.springframework.web.bind.annotation.ExceptionHandler Maven / Gradle / Ivy
/*
* Copyright 2002-2015 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.web.bind.annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Annotation for handling exceptions in specific handler classes and/or
* handler methods. Provides consistent style between Servlet and Portlet
* environments, with the semantics adapting to the concrete environment.
*
* Handler methods which are annotated with this annotation are allowed to
* have very flexible signatures. They may have parameters of the following
* types, in arbitrary order:
*
* - An exception argument: declared as a general Exception or as a more
* specific exception. This also serves as a mapping hint if the annotation
* itself does not narrow the exception types through its {@link #value()}.
*
- Request and/or response objects (Servlet API or Portlet API).
* You may choose any specific request/response type, e.g.
* {@link javax.servlet.ServletRequest} / {@link javax.servlet.http.HttpServletRequest}
* or {@link javax.portlet.PortletRequest} / {@link javax.portlet.ActionRequest} /
* {@link javax.portlet.RenderRequest}. Note that in the Portlet case,
* an explicitly declared action/render argument is also used for mapping
* specific request types onto a handler method (in case of no other
* information given that differentiates between action and render requests).
*
- Session object (Servlet API or Portlet API): either
* {@link javax.servlet.http.HttpSession} or {@link javax.portlet.PortletSession}.
* An argument of this type will enforce the presence of a corresponding session.
* As a consequence, such an argument will never be {@code null}.
* Note that session access may not be thread-safe, in particular in a
* Servlet environment: Consider switching the
* {@link org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter#setSynchronizeOnSession
* "synchronizeOnSession"} flag to "true" if multiple requests are allowed to
* access a session concurrently.
*
- {@link org.springframework.web.context.request.WebRequest} or
* {@link org.springframework.web.context.request.NativeWebRequest}.
* Allows for generic request parameter access as well as request/session
* attribute access, without ties to the native Servlet/Portlet API.
*
- {@link java.util.Locale} for the current request locale
* (determined by the most specific locale resolver available,
* i.e. the configured {@link org.springframework.web.servlet.LocaleResolver}
* in a Servlet environment and the portal locale in a Portlet environment).
*
- {@link java.io.InputStream} / {@link java.io.Reader} for access
* to the request's content. This will be the raw InputStream/Reader as
* exposed by the Servlet/Portlet API.
*
- {@link java.io.OutputStream} / {@link java.io.Writer} for generating
* the response's content. This will be the raw OutputStream/Writer as
* exposed by the Servlet/Portlet API.
*
- {@link org.springframework.ui.Model} as an alternative to returning
* a model map from the handler method. Note that the provided model is not
* pre-populated with regular model attributes and therefore always empty,
* as a convenience for preparing the model for an exception-specific view.
*
*
* The following return types are supported for handler methods:
*
* - A {@code ModelAndView} object (Servlet MVC or Portlet MVC).
*
- A {@link org.springframework.ui.Model} object, with the view name implicitly
* determined through a {@link org.springframework.web.servlet.RequestToViewNameTranslator}.
*
- A {@link java.util.Map} object for exposing a model,
* with the view name implicitly determined through a
* {@link org.springframework.web.servlet.RequestToViewNameTranslator}.
*
- A {@link org.springframework.web.servlet.View} object.
*
- A {@link String} value which is interpreted as view name.
*
- {@link ResponseBody @ResponseBody} annotated methods (Servlet-only)
* to set the response content. The return value will be converted to the
* response stream using
* {@linkplain org.springframework.http.converter.HttpMessageConverter message converters}.
*
- An {@link org.springframework.http.HttpEntity HttpEntity<?>} or
* {@link org.springframework.http.ResponseEntity ResponseEntity<?>} object
* (Servlet-only) to set response headers and content. The ResponseEntity body
* will be converted and written to the response stream using
* {@linkplain org.springframework.http.converter.HttpMessageConverter message converters}.
*
- {@code void} if the method handles the response itself (by
* writing the response content directly, declaring an argument of type
* {@link javax.servlet.ServletResponse} / {@link javax.servlet.http.HttpServletResponse}
* / {@link javax.portlet.RenderResponse} for that purpose)
* or if the view name is supposed to be implicitly determined through a
* {@link org.springframework.web.servlet.RequestToViewNameTranslator}
* (not declaring a response argument in the handler method signature;
* only applicable in a Servlet environment).
*
*
* In Servlet environments, you can combine the {@code ExceptionHandler} annotation
* with {@link ResponseStatus @ResponseStatus}, to define the response status
* for the HTTP response.
*
*
Note: In Portlet environments, {@code ExceptionHandler} annotated methods
* will only be called during the render and resource phases - just like
* {@link org.springframework.web.portlet.HandlerExceptionResolver} beans would.
* Exceptions carried over from the action and event phases will be invoked during
* the render phase as well, with exception handler methods having to be present
* on the controller class that defines the applicable render method.
*
* @author Arjen Poutsma
* @author Juergen Hoeller
* @since 3.0
* @see org.springframework.web.context.request.WebRequest
* @see org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerExceptionResolver
* @see org.springframework.web.portlet.mvc.annotation.AnnotationMethodHandlerExceptionResolver
*/
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface ExceptionHandler {
/**
* Exceptions handled by the annotated method. If empty, will default to any
* exceptions listed in the method argument list.
*/
Class[] value() default {};
}