| /* |
| * Copyright 2000-2013 JetBrains s.r.o. |
| * |
| * 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. |
| */ |
| |
| /* |
| * @author max |
| */ |
| package com.intellij.util.containers; |
| |
| import com.intellij.util.Consumer; |
| import com.intellij.util.containers.hash.EqualityPolicy; |
| import com.intellij.util.containers.hash.LinkedHashMap; |
| import org.jetbrains.annotations.NotNull; |
| import org.jetbrains.annotations.Nullable; |
| |
| import java.util.Map; |
| import java.util.Set; |
| |
| public class SLRUMap<K,V> { |
| protected final LinkedHashMap<K,V> myProtectedQueue; |
| protected final LinkedHashMap<K,V> myProbationalQueue; |
| |
| private final int myProtectedQueueSize; |
| private final int myProbationalQueueSize; |
| |
| private int probationalHits = 0; |
| private int protectedHits = 0; |
| private int misses = 0; |
| private static final int FACTOR = Integer.getInteger("idea.slru.factor", 1); |
| |
| public SLRUMap(final int protectedQueueSize, final int probationalQueueSize) { |
| this(protectedQueueSize, probationalQueueSize, (EqualityPolicy)EqualityPolicy.CANONICAL); |
| } |
| |
| public SLRUMap(final int protectedQueueSize, final int probationalQueueSize, EqualityPolicy hashingStrategy) { |
| myProtectedQueueSize = protectedQueueSize * FACTOR; |
| myProbationalQueueSize = probationalQueueSize * FACTOR; |
| |
| myProtectedQueue = new LinkedHashMap<K,V>(10, 0.6f, hashingStrategy, true) { |
| @Override |
| protected boolean removeEldestEntry(Map.Entry<K, V> eldest, K key, V value) { |
| if (size() > myProtectedQueueSize) { |
| myProbationalQueue.put(key, value); |
| return true; |
| } |
| |
| return false; |
| } |
| }; |
| |
| myProbationalQueue = new LinkedHashMap<K,V>(10, 0.6f, hashingStrategy, true) { |
| @Override |
| protected boolean removeEldestEntry(final Map.Entry<K, V> eldest, K key, V value) { |
| if (size() > myProbationalQueueSize) { |
| onDropFromCache(key, value); |
| return true; |
| } |
| return false; |
| } |
| }; |
| } |
| |
| @Nullable |
| public V get(K key) { |
| V value = myProtectedQueue.get(key); |
| if (value != null) { |
| protectedHits++; |
| return value; |
| } |
| |
| value = myProbationalQueue.remove(key); |
| if (value != null) { |
| probationalHits++; |
| putToProtectedQueue(key, value); |
| return value; |
| } |
| |
| misses++; |
| return null; |
| } |
| |
| protected void putToProtectedQueue(K key, V value) { |
| myProtectedQueue.put(getStableKey(key), value); |
| } |
| |
| public void put(K key, @NotNull V value) { |
| V oldValue = myProtectedQueue.remove(key); |
| if (oldValue != null) { |
| onDropFromCache(key, oldValue); |
| } |
| |
| oldValue = myProbationalQueue.put(getStableKey(key), value); |
| if (oldValue != null) { |
| onDropFromCache(key, oldValue); |
| } |
| } |
| |
| protected void onDropFromCache(K key, V value) {} |
| |
| public boolean remove(K key) { |
| V value = myProtectedQueue.remove(key); |
| if (value != null) { |
| onDropFromCache(key, value); |
| return true; |
| } |
| |
| value = myProbationalQueue.remove(key); |
| if (value != null) { |
| onDropFromCache(key, value); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| public void iterateKeys(final Consumer<K> keyConsumer) { |
| for (K key : myProtectedQueue.keySet()) { |
| keyConsumer.consume(key); |
| } |
| for (K key : myProbationalQueue.keySet()) { |
| keyConsumer.consume(key); |
| } |
| } |
| |
| public Set<Map.Entry<K, V>> entrySet() { |
| Set<Map.Entry<K, V>> set = new HashSet<Map.Entry<K,V>>(myProtectedQueue.entrySet()); |
| set.addAll(myProbationalQueue.entrySet()); |
| return set; |
| } |
| |
| public void clear() { |
| for (Map.Entry<K, V> entry : myProtectedQueue.entrySet()) { |
| onDropFromCache(entry.getKey(), entry.getValue()); |
| } |
| myProtectedQueue.clear(); |
| |
| for (Map.Entry<K, V> entry : myProbationalQueue.entrySet()) { |
| onDropFromCache(entry.getKey(), entry.getValue()); |
| } |
| myProbationalQueue.clear(); |
| } |
| |
| protected K getStableKey(K key) { |
| if (key instanceof ShareableKey) { |
| return (K)((ShareableKey)key).getStableCopy(); |
| } |
| |
| return key; |
| } |
| } |