org.springframework.web.servlet.mvc.method.annotation.MatrixVariableMethodArgumentResolver 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
*
* 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.mvc.method.annotation;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.springframework.core.MethodParameter;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import org.springframework.util.MultiValueMap;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.MissingMatrixVariableException;
import org.springframework.web.bind.ServletRequestBindingException;
import org.springframework.web.bind.annotation.MatrixVariable;
import org.springframework.web.bind.annotation.ValueConstants;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver;
import org.springframework.web.servlet.HandlerMapping;
/**
* Resolves arguments annotated with {@link MatrixVariable @MatrixVariable}.
*
* If the method parameter is of type {@link Map} it will by resolved by
* {@link MatrixVariableMapMethodArgumentResolver} instead unless the annotation
* specifies a name in which case it is considered to be a single attribute of
* type map (vs multiple attributes collected in a map).
*
* @author Rossen Stoyanchev
* @author Sam Brannen
* @since 3.2
*/
public class MatrixVariableMethodArgumentResolver extends AbstractNamedValueMethodArgumentResolver {
public MatrixVariableMethodArgumentResolver() {
super(null);
}
@Override
public boolean supportsParameter(MethodParameter parameter) {
if (!parameter.hasParameterAnnotation(MatrixVariable.class)) {
return false;
}
if (Map.class.isAssignableFrom(parameter.nestedIfOptional().getNestedParameterType())) {
MatrixVariable matrixVariable = parameter.getParameterAnnotation(MatrixVariable.class);
return (matrixVariable != null && StringUtils.hasText(matrixVariable.name()));
}
return true;
}
@Override
protected NamedValueInfo createNamedValueInfo(MethodParameter parameter) {
MatrixVariable ann = parameter.getParameterAnnotation(MatrixVariable.class);
Assert.state(ann != null, "No MatrixVariable annotation");
return new MatrixVariableNamedValueInfo(ann);
}
@Override
@SuppressWarnings("unchecked")
@Nullable
protected Object resolveName(String name, MethodParameter parameter, NativeWebRequest request) throws Exception {
Map> pathParameters = (Map>)
request.getAttribute(HandlerMapping.MATRIX_VARIABLES_ATTRIBUTE, RequestAttributes.SCOPE_REQUEST);
if (CollectionUtils.isEmpty(pathParameters)) {
return null;
}
MatrixVariable ann = parameter.getParameterAnnotation(MatrixVariable.class);
Assert.state(ann != null, "No MatrixVariable annotation");
String pathVar = ann.pathVar();
List paramValues = null;
if (!pathVar.equals(ValueConstants.DEFAULT_NONE)) {
if (pathParameters.containsKey(pathVar)) {
paramValues = pathParameters.get(pathVar).get(name);
}
}
else {
boolean found = false;
paramValues = new ArrayList<>();
for (MultiValueMap params : pathParameters.values()) {
if (params.containsKey(name)) {
if (found) {
String paramType = parameter.getNestedParameterType().getName();
throw new ServletRequestBindingException(
"Found more than one match for URI path parameter '" + name +
"' for parameter type [" + paramType + "]. Use 'pathVar' attribute to disambiguate.");
}
paramValues.addAll(params.get(name));
found = true;
}
}
}
if (CollectionUtils.isEmpty(paramValues)) {
return null;
}
else if (paramValues.size() == 1) {
return paramValues.get(0);
}
else {
return paramValues;
}
}
@Override
protected void handleMissingValue(String name, MethodParameter parameter) throws ServletRequestBindingException {
throw new MissingMatrixVariableException(name, parameter);
}
private static final class MatrixVariableNamedValueInfo extends NamedValueInfo {
private MatrixVariableNamedValueInfo(MatrixVariable annotation) {
super(annotation.name(), annotation.required(), annotation.defaultValue());
}
}
}