/*
* Copyright 2002-2016 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 java.util.Collections;
import java.util.List;
import java.util.Map;
import org.springframework.core.MethodParameter;
import org.springframework.core.ResolvableType;
import org.springframework.util.CollectionUtils;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.MatrixVariable;
import org.springframework.web.bind.annotation.ValueConstants;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.ModelAndViewContainer;
import org.springframework.web.servlet.HandlerMapping;
/**
* Resolves method arguments of type Map annotated with
* {@link MatrixVariable @MatrixVariable} where the annotation does not
* specify a name. If a name is specified then the argument will by resolved by the
* {@link MatrixVariableMethodArgumentResolver} instead.
*
* @author Rossen Stoyanchev
* @since 3.2
*/
public class MatrixVariableMapMethodArgumentResolver implements HandlerMethodArgumentResolver {
@Override
public boolean supportsParameter(MethodParameter parameter) {
MatrixVariable matrixVariable = parameter.getParameterAnnotation(MatrixVariable.class);
if (matrixVariable != null) {
if (Map.class.isAssignableFrom(parameter.getParameterType())) {
return !StringUtils.hasText(matrixVariable.name());
}
}
return false;
}
@Override
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
NativeWebRequest request, WebDataBinderFactory binderFactory) throws Exception {
@SuppressWarnings("unchecked")
Map<String, MultiValueMap<String, String>> matrixVariables =
(Map<String, MultiValueMap<String, String>>) request.getAttribute(
HandlerMapping.MATRIX_VARIABLES_ATTRIBUTE, RequestAttributes.SCOPE_REQUEST);
if (CollectionUtils.isEmpty(matrixVariables)) {
return Collections.emptyMap();
}
MultiValueMap<String, String> map = new LinkedMultiValueMap<>();
String pathVariable = parameter.getParameterAnnotation(MatrixVariable.class).pathVar();
if (!pathVariable.equals(ValueConstants.DEFAULT_NONE)) {
MultiValueMap<String, String> mapForPathVariable = matrixVariables.get(pathVariable);
if (mapForPathVariable == null) {
return Collections.emptyMap();
}
map.putAll(mapForPathVariable);
}
else {
for (MultiValueMap<String, String> vars : matrixVariables.values()) {
for (String name : vars.keySet()) {
for (String value : vars.get(name)) {
map.add(name, value);
}
}
}
}
return (isSingleValueMap(parameter) ? map.toSingleValueMap() : map);
}
private boolean isSingleValueMap(MethodParameter parameter) {
if (!MultiValueMap.class.isAssignableFrom(parameter.getParameterType())) {
ResolvableType[] genericTypes = ResolvableType.forMethodParameter(parameter).getGenerics();
if (genericTypes.length == 2) {
return !List.class.isAssignableFrom(genericTypes[1].getRawClass());
}
}
return false;
}
}