org.springframework.cache.interceptor.CacheOperationExpressionEvaluator 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.cache.interceptor;
import java.lang.reflect.Method;
import java.util.Collection;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.cache.Cache;
import org.springframework.context.expression.AnnotatedElementKey;
import org.springframework.context.expression.BeanFactoryResolver;
import org.springframework.context.expression.CachedExpressionEvaluator;
import org.springframework.expression.EvaluationContext;
import org.springframework.expression.Expression;
import org.springframework.lang.Nullable;
/**
* Utility class handling the SpEL expression parsing.
* Meant to be used as a reusable, thread-safe component.
*
* Performs internal caching for performance reasons
* using {@link AnnotatedElementKey}.
*
* @author Costin Leau
* @author Phillip Webb
* @author Sam Brannen
* @author Stephane Nicoll
* @since 3.1
*/
class CacheOperationExpressionEvaluator extends CachedExpressionEvaluator {
/**
* Indicate that there is no result variable.
*/
public static final Object NO_RESULT = new Object();
/**
* Indicate that the result variable cannot be used at all.
*/
public static final Object RESULT_UNAVAILABLE = new Object();
/**
* The name of the variable holding the result object.
*/
public static final String RESULT_VARIABLE = "result";
private final Map keyCache = new ConcurrentHashMap<>(64);
private final Map conditionCache = new ConcurrentHashMap<>(64);
private final Map unlessCache = new ConcurrentHashMap<>(64);
/**
* Create an {@link EvaluationContext}.
* @param caches the current caches
* @param method the method
* @param args the method arguments
* @param target the target object
* @param targetClass the target class
* @param result the return value (can be {@code null}) or
* {@link #NO_RESULT} if there is no return at this time
* @return the evaluation context
*/
public EvaluationContext createEvaluationContext(Collection caches,
Method method, Object[] args, Object target, Class targetClass, Method targetMethod,
@Nullable Object result, @Nullable BeanFactory beanFactory) {
CacheExpressionRootObject rootObject = new CacheExpressionRootObject(
caches, method, args, target, targetClass);
CacheEvaluationContext evaluationContext = new CacheEvaluationContext(
rootObject, targetMethod, args, getParameterNameDiscoverer());
if (result == RESULT_UNAVAILABLE) {
evaluationContext.addUnavailableVariable(RESULT_VARIABLE);
}
else if (result != NO_RESULT) {
evaluationContext.setVariable(RESULT_VARIABLE, result);
}
if (beanFactory != null) {
evaluationContext.setBeanResolver(new BeanFactoryResolver(beanFactory));
}
return evaluationContext;
}
@Nullable
public Object key(String keyExpression, AnnotatedElementKey methodKey, EvaluationContext evalContext) {
return getExpression(this.keyCache, methodKey, keyExpression).getValue(evalContext);
}
public boolean condition(String conditionExpression, AnnotatedElementKey methodKey, EvaluationContext evalContext) {
return (Boolean.TRUE.equals(getExpression(this.conditionCache, methodKey, conditionExpression).getValue(
evalContext, Boolean.class)));
}
public boolean unless(String unlessExpression, AnnotatedElementKey methodKey, EvaluationContext evalContext) {
return (Boolean.TRUE.equals(getExpression(this.unlessCache, methodKey, unlessExpression).getValue(
evalContext, Boolean.class)));
}
/**
* Clear all caches.
*/
void clear() {
this.keyCache.clear();
this.conditionCache.clear();
this.unlessCache.clear();
}
}