org.springframework.cache.jcache.interceptor.AbstractFallbackJCacheOperationSource 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
*
* 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.cache.jcache.interceptor;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.aop.support.AopUtils;
import org.springframework.core.MethodClassKey;
import org.springframework.lang.Nullable;
/**
* Abstract implementation of {@link JCacheOperationSource} that caches attributes
* for methods and implements a fallback policy: 1. specific target method;
* 2. declaring method.
*
* This implementation caches attributes by method after they are first used.
*
* @author Stephane Nicoll
* @author Juergen Hoeller
* @since 4.1
* @see org.springframework.cache.interceptor.AbstractFallbackCacheOperationSource
*/
public abstract class AbstractFallbackJCacheOperationSource implements JCacheOperationSource {
/**
* Canonical value held in cache to indicate no caching attribute was
* found for this method and we don't need to look again.
*/
private static final Object NULL_CACHING_ATTRIBUTE = new Object();
protected final Log logger = LogFactory.getLog(getClass());
private final Map cache = new ConcurrentHashMap<>(1024);
@Override
public JCacheOperation getCacheOperation(Method method, @Nullable Class targetClass) {
MethodClassKey cacheKey = new MethodClassKey(method, targetClass);
Object cached = this.cache.get(cacheKey);
if (cached != null) {
return (cached != NULL_CACHING_ATTRIBUTE ? (JCacheOperation) cached : null);
}
else {
JCacheOperation operation = computeCacheOperation(method, targetClass);
if (operation != null) {
if (logger.isDebugEnabled()) {
logger.debug("Adding cacheable method '" + method.getName() + "' with operation: " + operation);
}
this.cache.put(cacheKey, operation);
}
else {
this.cache.put(cacheKey, NULL_CACHING_ATTRIBUTE);
}
return operation;
}
}
@Nullable
private JCacheOperation computeCacheOperation(Method method, @Nullable Class targetClass) {
// Don't allow no-public methods as required.
if (allowPublicMethodsOnly() && !Modifier.isPublic(method.getModifiers())) {
return null;
}
// The method may be on an interface, but we need attributes from the target class.
// If the target class is null, the method will be unchanged.
Method specificMethod = AopUtils.getMostSpecificMethod(method, targetClass);
// First try is the method in the target class.
JCacheOperation operation = findCacheOperation(specificMethod, targetClass);
if (operation != null) {
return operation;
}
if (specificMethod != method) {
// Fallback is to look at the original method.
operation = findCacheOperation(method, targetClass);
if (operation != null) {
return operation;
}
}
return null;
}
/**
* Subclasses need to implement this to return the caching operation
* for the given method, if any.
* @param method the method to retrieve the operation for
* @param targetType the target class
* @return the cache operation associated with this method
* (or {@code null} if none)
*/
@Nullable
protected abstract JCacheOperation findCacheOperation(Method method, @Nullable Class targetType);
/**
* Should only public methods be allowed to have caching semantics?
* The default implementation returns {@code false}.
*/
protected boolean allowPublicMethodsOnly() {
return false;
}
}