org.springframework.web.method.support.HandlerMethodArgumentResolverComposite Maven / Gradle / Ivy
/*
* 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.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.core.MethodParameter;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
/**
* Resolves method parameters by delegating to a list of registered {@link HandlerMethodArgumentResolver}s.
* Previously resolved method parameters are cached for faster lookups.
*
* @author Rossen Stoyanchev
* @author Juergen Hoeller
* @since 3.1
*/
public class HandlerMethodArgumentResolverComposite implements HandlerMethodArgumentResolver {
protected final Log logger = LogFactory.getLog(getClass());
private final List argumentResolvers =
new LinkedList();
private final Map argumentResolverCache =
new ConcurrentHashMap(256);
/**
* Add the given {@link HandlerMethodArgumentResolver}.
*/
public HandlerMethodArgumentResolverComposite addResolver(HandlerMethodArgumentResolver resolver) {
this.argumentResolvers.add(resolver);
return this;
}
/**
* Add the given {@link HandlerMethodArgumentResolver}s.
* @since 4.3
*/
public HandlerMethodArgumentResolverComposite addResolvers(HandlerMethodArgumentResolver... resolvers) {
if (resolvers != null) {
for (HandlerMethodArgumentResolver resolver : resolvers) {
this.argumentResolvers.add(resolver);
}
}
return this;
}
/**
* Add the given {@link HandlerMethodArgumentResolver}s.
*/
public HandlerMethodArgumentResolverComposite addResolvers(List resolvers) {
if (resolvers != null) {
for (HandlerMethodArgumentResolver resolver : resolvers) {
this.argumentResolvers.add(resolver);
}
}
return this;
}
/**
* Return a read-only list with the contained resolvers, or an empty list.
*/
public List getResolvers() {
return Collections.unmodifiableList(this.argumentResolvers);
}
/**
* Clear the list of configured resolvers.
* @since 4.3
*/
public void clear() {
this.argumentResolvers.clear();
}
/**
* Whether the given {@linkplain MethodParameter method parameter} is supported by any registered
* {@link HandlerMethodArgumentResolver}.
*/
@Override
public boolean supportsParameter(MethodParameter parameter) {
return (getArgumentResolver(parameter) != null);
}
/**
* Iterate over registered {@link HandlerMethodArgumentResolver}s and invoke the one that supports it.
* @throws IllegalStateException if no suitable {@link HandlerMethodArgumentResolver} is found.
*/
@Override
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
HandlerMethodArgumentResolver resolver = getArgumentResolver(parameter);
if (resolver == null) {
throw new IllegalArgumentException("Unknown parameter type [" + parameter.getParameterType().getName() + "]");
}
return resolver.resolveArgument(parameter, mavContainer, webRequest, binderFactory);
}
/**
* Find a registered {@link HandlerMethodArgumentResolver} that supports the given method parameter.
*/
private HandlerMethodArgumentResolver getArgumentResolver(MethodParameter parameter) {
HandlerMethodArgumentResolver result = this.argumentResolverCache.get(parameter);
if (result == null) {
for (HandlerMethodArgumentResolver methodArgumentResolver : this.argumentResolvers) {
if (logger.isTraceEnabled()) {
logger.trace("Testing if argument resolver [" + methodArgumentResolver + "] supports [" +
parameter.getGenericParameterType() + "]");
}
if (methodArgumentResolver.supportsParameter(parameter)) {
result = methodArgumentResolver;
this.argumentResolverCache.put(parameter, result);
break;
}
}
}
return result;
}
}