org.springframework.web.method.annotation.RequestHeaderMethodArgumentResolver Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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.method.annotation;
import java.util.Map;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.core.MethodParameter;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.web.bind.MissingRequestHeaderException;
import org.springframework.web.bind.ServletRequestBindingException;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.RequestHeader;
import org.springframework.web.context.request.NativeWebRequest;
/**
* Resolves method arguments annotated with {@code @RequestHeader} except for
* {@link Map} arguments. See {@link RequestHeaderMapMethodArgumentResolver} for
* details on {@link Map} arguments annotated with {@code @RequestHeader}.
*
* An {@code @RequestHeader} is a named value resolved from a request header.
* It has a required flag and a default value to fall back on when the request
* header does not exist.
*
*
A {@link WebDataBinder} is invoked to apply type conversion to resolved
* request header values that don't yet match the method parameter type.
*
* @author Arjen Poutsma
* @author Rossen Stoyanchev
* @since 3.1
*/
public class RequestHeaderMethodArgumentResolver extends AbstractNamedValueMethodArgumentResolver {
/**
* Create a new {@link RequestHeaderMethodArgumentResolver} instance.
* @param beanFactory a bean factory to use for resolving ${...}
* placeholder and #{...} SpEL expressions in default values;
* or {@code null} if default values are not expected to have expressions
*/
public RequestHeaderMethodArgumentResolver(@Nullable ConfigurableBeanFactory beanFactory) {
super(beanFactory);
}
@Override
public boolean supportsParameter(MethodParameter parameter) {
return (parameter.hasParameterAnnotation(RequestHeader.class) &&
!Map.class.isAssignableFrom(parameter.nestedIfOptional().getNestedParameterType()));
}
@Override
protected NamedValueInfo createNamedValueInfo(MethodParameter parameter) {
RequestHeader ann = parameter.getParameterAnnotation(RequestHeader.class);
Assert.state(ann != null, "No RequestHeader annotation");
return new RequestHeaderNamedValueInfo(ann);
}
@Override
@Nullable
protected Object resolveName(String name, MethodParameter parameter, NativeWebRequest request) throws Exception {
String[] headerValues = request.getHeaderValues(name);
if (headerValues != null) {
return (headerValues.length == 1 ? headerValues[0] : headerValues);
}
else {
return null;
}
}
@Override
protected void handleMissingValue(String name, MethodParameter parameter) throws ServletRequestBindingException {
throw new MissingRequestHeaderException(name, parameter);
}
private static final class RequestHeaderNamedValueInfo extends NamedValueInfo {
private RequestHeaderNamedValueInfo(RequestHeader annotation) {
super(annotation.name(), annotation.required(), annotation.defaultValue());
}
}
}