/*
* 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
*
* http://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.mvc.method.annotation;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.core.MethodParameter;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.context.request.async.WebAsyncTask;
import org.springframework.web.context.request.async.WebAsyncUtils;
import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
import org.springframework.web.method.support.ModelAndViewContainer;
/**
* Handles return values of type {@link WebAsyncTask}.
*
* @author Rossen Stoyanchev
* @since 3.2
*/
public class AsyncTaskMethodReturnValueHandler implements HandlerMethodReturnValueHandler {
private final BeanFactory beanFactory;
public AsyncTaskMethodReturnValueHandler(BeanFactory beanFactory) {
this.beanFactory = beanFactory;
}
@Override
public boolean supportsReturnType(MethodParameter returnType) {
return WebAsyncTask.class.isAssignableFrom(returnType.getParameterType());
}
@Override
public void handleReturnValue(Object returnValue, MethodParameter returnType,
ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {
if (returnValue == null) {
mavContainer.setRequestHandled(true);
return;
}
WebAsyncTask<?> webAsyncTask = (WebAsyncTask<?>) returnValue;
webAsyncTask.setBeanFactory(this.beanFactory);
WebAsyncUtils.getAsyncManager(webRequest).startCallableProcessing(webAsyncTask, mavContainer);
}
}