org.springframework.cache.annotation.AbstractCachingConfiguration Maven / Gradle / Ivy
/*
* Copyright 2002-2021 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.cache.annotation;
import java.util.List;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.stream.Collectors;
import org.springframework.beans.factory.ObjectProvider;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.CacheManager;
import org.springframework.cache.interceptor.CacheErrorHandler;
import org.springframework.cache.interceptor.CacheResolver;
import org.springframework.cache.interceptor.KeyGenerator;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.ImportAware;
import org.springframework.core.annotation.AnnotationAttributes;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.lang.Nullable;
import org.springframework.util.CollectionUtils;
import org.springframework.util.function.SingletonSupplier;
/**
* Abstract base {@code @Configuration} class providing common structure
* for enabling Spring's annotation-driven cache management capability.
*
* @author Chris Beams
* @author Stephane Nicoll
* @author Juergen Hoeller
* @since 3.1
* @see EnableCaching
*/
@Configuration(proxyBeanMethods = false)
public abstract class AbstractCachingConfiguration implements ImportAware {
@Nullable
protected AnnotationAttributes enableCaching;
@Nullable
protected Supplier cacheManager;
@Nullable
protected Supplier cacheResolver;
@Nullable
protected Supplier keyGenerator;
@Nullable
protected Supplier errorHandler;
@Override
public void setImportMetadata(AnnotationMetadata importMetadata) {
this.enableCaching = AnnotationAttributes.fromMap(
importMetadata.getAnnotationAttributes(EnableCaching.class.getName()));
if (this.enableCaching == null) {
throw new IllegalArgumentException(
"@EnableCaching is not present on importing class " + importMetadata.getClassName());
}
}
@Autowired
void setConfigurers(ObjectProvider configurers) {
Supplier configurer = () -> {
List candidates = configurers.stream().collect(Collectors.toList());
if (CollectionUtils.isEmpty(candidates)) {
return null;
}
if (candidates.size() > 1) {
throw new IllegalStateException(candidates.size() + " implementations of " +
"CachingConfigurer were found when only 1 was expected. " +
"Refactor the configuration such that CachingConfigurer is " +
"implemented only once or not at all.");
}
return candidates.get(0);
};
useCachingConfigurer(new CachingConfigurerSupplier(configurer));
}
/**
* Extract the configuration from the nominated {@link CachingConfigurer}.
*/
protected void useCachingConfigurer(CachingConfigurerSupplier cachingConfigurerSupplier) {
this.cacheManager = cachingConfigurerSupplier.adapt(CachingConfigurer::cacheManager);
this.cacheResolver = cachingConfigurerSupplier.adapt(CachingConfigurer::cacheResolver);
this.keyGenerator = cachingConfigurerSupplier.adapt(CachingConfigurer::keyGenerator);
this.errorHandler = cachingConfigurerSupplier.adapt(CachingConfigurer::errorHandler);
}
protected static class CachingConfigurerSupplier {
private final Supplier supplier;
public CachingConfigurerSupplier(Supplier supplier) {
this.supplier = SingletonSupplier.of(supplier);
}
/**
* Adapt the {@link CachingConfigurer} supplier to another supplier
* provided by the specified mapping function. If the underlying
* {@link CachingConfigurer} is {@code null}, {@code null} is returned
* and the mapping function is not invoked.
* @param provider the provider to use to adapt the supplier
* @param the type of the supplier
* @return another supplier mapped by the specified function
*/
@Nullable
public Supplier adapt(Function provider) {
return () -> {
CachingConfigurer cachingConfigurer = this.supplier.get();
return (cachingConfigurer != null ? provider.apply(cachingConfigurer) : null);
};
}
}
}