/*
* Copyright 2014-2017 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
*
* 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.data.rest.webmvc.support;
import static org.springframework.http.HttpHeaders.*;
import java.util.Optional;
import org.springframework.core.MethodParameter;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.ModelAndViewContainer;
/**
* {@link HandlerMethodArgumentResolver} to resolve If-Match headers for optimistic locking handling {@link IfMatch}.
*
* @author Pablo Lozano
* @author Oliver Gierke
*/
public class ETagArgumentResolver implements HandlerMethodArgumentResolver {
/*
* (non-Javadoc)
* @see org.springframework.web.method.support.HandlerMethodArgumentResolver#supportsParameter(org.springframework.core.MethodParameter)
*/
@Override
public boolean supportsParameter(MethodParameter parameter) {
return parameter.getParameterType().equals(ETag.class);
}
/*
* (non-Javadoc)
* @see org.springframework.web.method.support.HandlerMethodArgumentResolver#resolveArgument(org.springframework.core.MethodParameter, org.springframework.web.method.support.ModelAndViewContainer, org.springframework.web.context.request.NativeWebRequest, org.springframework.web.bind.support.WebDataBinderFactory)
*/
@Override
public ETag resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
return ETag.from(Optional.ofNullable(webRequest.getHeader(IF_MATCH)));
}
}