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The Core Camel Java DSL based router
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.camel.util;
/**
* A cache that uses a near optional LRU Cache using {@link java.lang.ref.WeakReference}.
*
* The Cache is implemented by Caffeine which provides an efficient cache.
*
* This implementation uses {@link java.lang.ref.WeakReference} for stored values in the cache, to support the JVM
* when it wants to reclaim objects for example during garbage collection. Therefore this implementation does
* not support all the {@link java.util.Map} methods.
*
* The following methods is only be be used:
*
* - containsKey - To determine if the key is in the cache and refers to a value
* - entrySet - To return a set of all the entries (as key/value paris)
* - get - To get a value from the cache
* - isEmpty - To determine if the cache contains any values
* - keySet - To return a set of the current keys which refers to a value
* - put - To add a value to the cache
* - putAll - To add values to the cache
* - remove - To remove a value from the cache by its key
* - size - To get the current size
* - values - To return a copy of all the value in a list
*
*
* The {@link #containsValue(Object)} method should not be used as it's not adjusted to check
* for the existence of a value without catering for the soft references.
*
* Notice that if the JVM reclaim memory the content of this cache may be garbage collected, without any
* eviction notifications.
*
* @see LRUCache
* @see LRUSoftCache
*/
public class LRUWeakCache extends LRUCache {
public LRUWeakCache(int maximumCacheSize) {
this(16, maximumCacheSize);
}
public LRUWeakCache(int initialCapacity, int maximumCacheSize) {
super(initialCapacity, maximumCacheSize, false, false, true, false);
}
@Override
public String toString() {
return "LRUWeakCache@" + ObjectHelper.getIdentityHashCode(this);
}
}