org.springframework.web.servlet.handler.AbstractHandlerMethodExceptionResolver Maven / Gradle / Ivy
/*
* Copyright 2002-2017 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.servlet.handler;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.lang.Nullable;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.ModelAndView;
/**
* Abstract base class for
* {@link org.springframework.web.servlet.HandlerExceptionResolver HandlerExceptionResolver}
* implementations that support handling exceptions from handlers of type {@link HandlerMethod}.
*
* @author Rossen Stoyanchev
* @since 3.1
*/
public abstract class AbstractHandlerMethodExceptionResolver extends AbstractHandlerExceptionResolver {
/**
* Checks if the handler is a {@link HandlerMethod} and then delegates to the
* base class implementation of {@code #shouldApplyTo(HttpServletRequest, Object)}
* passing the bean of the {@code HandlerMethod}. Otherwise returns {@code false}.
*/
@Override
protected boolean shouldApplyTo(HttpServletRequest request, @Nullable Object handler) {
if (handler == null) {
return super.shouldApplyTo(request, null);
}
else if (handler instanceof HandlerMethod) {
HandlerMethod handlerMethod = (HandlerMethod) handler;
handler = handlerMethod.getBean();
return super.shouldApplyTo(request, handler);
}
else {
return false;
}
}
@Override
@Nullable
protected final ModelAndView doResolveException(
HttpServletRequest request, HttpServletResponse response, @Nullable Object handler, Exception ex) {
return doResolveHandlerMethodException(request, response, (HandlerMethod) handler, ex);
}
/**
* Actually resolve the given exception that got thrown during on handler execution,
* returning a ModelAndView that represents a specific error page if appropriate.
* May be overridden in subclasses, in order to apply specific exception checks.
* Note that this template method will be invoked after checking whether this
* resolved applies ("mappedHandlers" etc), so an implementation may simply proceed
* with its actual exception handling.
* @param request current HTTP request
* @param response current HTTP response
* @param handlerMethod the executed handler method, or {@code null} if none chosen at the time
* of the exception (for example, if multipart resolution failed)
* @param ex the exception that got thrown during handler execution
* @return a corresponding ModelAndView to forward to, or {@code null} for default processing
*/
@Nullable
protected abstract ModelAndView doResolveHandlerMethodException(
HttpServletRequest request, HttpServletResponse response, @Nullable HandlerMethod handlerMethod, Exception ex);
}