/*
* 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.method.support;
import java.util.Collection;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import org.springframework.core.MethodParameter;
import org.springframework.core.convert.ConversionService;
import org.springframework.format.support.DefaultFormattingConversionService;
import org.springframework.util.Assert;
import org.springframework.web.util.UriComponentsBuilder;
/**
* A {@link UriComponentsContributor} containing a list of other contributors
* to delegate and also encapsulating a specific {@link ConversionService} to
* use for formatting method argument values to Strings.
*
* @author Rossen Stoyanchev
* @since 4.0
*/
public class CompositeUriComponentsContributor implements UriComponentsContributor {
private final List<Object> contributors = new LinkedList<>();
private final ConversionService conversionService;
/**
* Create an instance from a collection of {@link UriComponentsContributor}s or
* {@link HandlerMethodArgumentResolver}s. Since both of these tend to be implemented
* by the same class, the most convenient option is to obtain the configured
* {@code HandlerMethodArgumentResolvers} in {@code RequestMappingHandlerAdapter}
* and provide that to this constructor.
* @param contributors a collection of {@link UriComponentsContributor}
* or {@link HandlerMethodArgumentResolver}s.
*/
public CompositeUriComponentsContributor(UriComponentsContributor... contributors) {
Collections.addAll(this.contributors, contributors);
this.conversionService = new DefaultFormattingConversionService();
}
/**
* Create an instance from a collection of {@link UriComponentsContributor}s or
* {@link HandlerMethodArgumentResolver}s. Since both of these tend to be implemented
* by the same class, the most convenient option is to obtain the configured
* {@code HandlerMethodArgumentResolvers} in {@code RequestMappingHandlerAdapter}
* and provide that to this constructor.
* @param contributors a collection of {@link UriComponentsContributor}
* or {@link HandlerMethodArgumentResolver}s.
*/
public CompositeUriComponentsContributor(Collection<?> contributors) {
this(contributors, null);
}
/**
* Create an instance from a collection of {@link UriComponentsContributor}s or
* {@link HandlerMethodArgumentResolver}s. Since both of these tend to be implemented
* by the same class, the most convenient option is to obtain the configured
* {@code HandlerMethodArgumentResolvers} in the {@code RequestMappingHandlerAdapter}
* and provide that to this constructor.
* <p>If the {@link ConversionService} argument is {@code null},
* {@link org.springframework.format.support.DefaultFormattingConversionService}
* will be used by default.
* @param contributors a collection of {@link UriComponentsContributor}
* or {@link HandlerMethodArgumentResolver}s.
* @param cs a ConversionService to use when method argument values
* need to be formatted as Strings before being added to the URI
*/
public CompositeUriComponentsContributor(Collection<?> contributors, ConversionService cs) {
Assert.notNull(contributors, "'uriComponentsContributors' must not be null");
this.contributors.addAll(contributors);
this.conversionService = (cs != null ? cs : new DefaultFormattingConversionService());
}
public boolean hasContributors() {
return this.contributors.isEmpty();
}
@Override
public boolean supportsParameter(MethodParameter parameter) {
for (Object c : this.contributors) {
if (c instanceof UriComponentsContributor) {
UriComponentsContributor contributor = (UriComponentsContributor) c;
if (contributor.supportsParameter(parameter)) {
return true;
}
}
else if (c instanceof HandlerMethodArgumentResolver) {
if (((HandlerMethodArgumentResolver) c).supportsParameter(parameter)) {
return false;
}
}
}
return false;
}
@Override
public void contributeMethodArgument(MethodParameter parameter, Object value,
UriComponentsBuilder builder, Map<String, Object> uriVariables, ConversionService conversionService) {
for (Object contributor : this.contributors) {
if (contributor instanceof UriComponentsContributor) {
UriComponentsContributor ucc = (UriComponentsContributor) contributor;
if (ucc.supportsParameter(parameter)) {
ucc.contributeMethodArgument(parameter, value, builder, uriVariables, conversionService);
break;
}
}
else if (contributor instanceof HandlerMethodArgumentResolver) {
if (((HandlerMethodArgumentResolver) contributor).supportsParameter(parameter)) {
break;
}
}
}
}
/**
* An overloaded method that uses the ConversionService created at construction.
*/
public void contributeMethodArgument(MethodParameter parameter, Object value, UriComponentsBuilder builder,
Map<String, Object> uriVariables) {
this.contributeMethodArgument(parameter, value, builder, uriVariables, this.conversionService);
}
}