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-rw-r--r--include/utils/GenerationCache.h247
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diff --git a/include/utils/GenerationCache.h b/include/utils/GenerationCache.h
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--- a/include/utils/GenerationCache.h
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@@ -1,247 +0,0 @@
-/*
- * Copyright (C) 2010 The Android Open Source Project
- *
- * 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.
- */
-
-#ifndef ANDROID_UTILS_GENERATION_CACHE_H
-#define ANDROID_UTILS_GENERATION_CACHE_H
-
-#include <utils/KeyedVector.h>
-#include <utils/RefBase.h>
-
-namespace android {
-
-/**
- * GenerationCache callback used when an item is removed
- */
-template<typename EntryKey, typename EntryValue>
-class OnEntryRemoved {
-public:
- virtual ~OnEntryRemoved() { };
- virtual void operator()(EntryKey& key, EntryValue& value) = 0;
-}; // class OnEntryRemoved
-
-template<typename EntryKey, typename EntryValue>
-struct Entry: public LightRefBase<Entry<EntryKey, EntryValue> > {
- Entry(const Entry<EntryKey, EntryValue>& e) :
- key(e.key), value(e.value),
- parent(e.parent), child(e.child) { }
- Entry(const EntryKey& key, const EntryValue& value) :
- key(key), value(value) { }
-
- EntryKey key;
- EntryValue value;
-
- sp<Entry<EntryKey, EntryValue> > parent; // next older entry
- sp<Entry<EntryKey, EntryValue> > child; // next younger entry
-}; // struct Entry
-
-/**
- * A LRU type cache
- */
-template<typename K, typename V>
-class GenerationCache {
-public:
- GenerationCache(uint32_t maxCapacity);
- virtual ~GenerationCache();
-
- enum Capacity {
- kUnlimitedCapacity,
- };
-
- void setOnEntryRemovedListener(OnEntryRemoved<K, V>* listener);
-
- size_t size() const;
-
- void clear();
-
- bool contains(const K& key) const;
- const K& getKeyAt(size_t index) const;
- const V& getValueAt(size_t index) const;
-
- const V& get(const K& key);
- bool put(const K& key, const V& value);
-
- void removeAt(ssize_t index);
- bool remove(const K& key);
- bool removeOldest();
-
-private:
- KeyedVector<K, sp<Entry<K, V> > > mCache;
- uint32_t mMaxCapacity;
-
- OnEntryRemoved<K, V>* mListener;
-
- sp<Entry<K, V> > mOldest;
- sp<Entry<K, V> > mYoungest;
-
- void attachToCache(const sp<Entry<K, V> >& entry);
- void detachFromCache(const sp<Entry<K, V> >& entry);
-
- const V mNullValue;
-}; // class GenerationCache
-
-template<typename K, typename V>
-GenerationCache<K, V>::GenerationCache(uint32_t maxCapacity): mMaxCapacity(maxCapacity),
- mListener(NULL), mNullValue(NULL) {
-};
-
-template<typename K, typename V>
-GenerationCache<K, V>::~GenerationCache() {
- clear();
-};
-
-template<typename K, typename V>
-uint32_t GenerationCache<K, V>::size() const {
- return mCache.size();
-}
-
-/**
- * Should be set by the user of the Cache so that the callback is called whenever an item is
- * removed from the cache
- */
-template<typename K, typename V>
-void GenerationCache<K, V>::setOnEntryRemovedListener(OnEntryRemoved<K, V>* listener) {
- mListener = listener;
-}
-
-template<typename K, typename V>
-void GenerationCache<K, V>::clear() {
- if (mListener) {
- for (uint32_t i = 0; i < mCache.size(); i++) {
- sp<Entry<K, V> > entry = mCache.valueAt(i);
- if (mListener) {
- (*mListener)(entry->key, entry->value);
- }
- }
- }
- mCache.clear();
- mYoungest.clear();
- mOldest.clear();
-}
-
-template<typename K, typename V>
-bool GenerationCache<K, V>::contains(const K& key) const {
- return mCache.indexOfKey(key) >= 0;
-}
-
-template<typename K, typename V>
-const K& GenerationCache<K, V>::getKeyAt(size_t index) const {
- return mCache.keyAt(index);
-}
-
-template<typename K, typename V>
-const V& GenerationCache<K, V>::getValueAt(size_t index) const {
- return mCache.valueAt(index)->value;
-}
-
-template<typename K, typename V>
-const V& GenerationCache<K, V>::get(const K& key) {
- ssize_t index = mCache.indexOfKey(key);
- if (index >= 0) {
- const sp<Entry<K, V> >& entry = mCache.valueAt(index);
- detachFromCache(entry);
- attachToCache(entry);
- return entry->value;
- }
-
- return mNullValue;
-}
-
-template<typename K, typename V>
-bool GenerationCache<K, V>::put(const K& key, const V& value) {
- if (mMaxCapacity != kUnlimitedCapacity && mCache.size() >= mMaxCapacity) {
- removeOldest();
- }
-
- ssize_t index = mCache.indexOfKey(key);
- if (index < 0) {
- sp<Entry<K, V> > entry = new Entry<K, V>(key, value);
- mCache.add(key, entry);
- attachToCache(entry);
- return true;
- }
-
- return false;
-}
-
-template<typename K, typename V>
-bool GenerationCache<K, V>::remove(const K& key) {
- ssize_t index = mCache.indexOfKey(key);
- if (index >= 0) {
- removeAt(index);
- return true;
- }
-
- return false;
-}
-
-template<typename K, typename V>
-void GenerationCache<K, V>::removeAt(ssize_t index) {
- sp<Entry<K, V> > entry = mCache.valueAt(index);
- if (mListener) {
- (*mListener)(entry->key, entry->value);
- }
- mCache.removeItemsAt(index, 1);
- detachFromCache(entry);
-}
-
-template<typename K, typename V>
-bool GenerationCache<K, V>::removeOldest() {
- if (mOldest.get()) {
- ssize_t index = mCache.indexOfKey(mOldest->key);
- if (index >= 0) {
- removeAt(index);
- return true;
- }
- ALOGE("GenerationCache: removeOldest failed to find the item in the cache "
- "with the given key, but we know it must be in there. "
- "Is the key comparator kaput?");
- }
-
- return false;
-}
-
-template<typename K, typename V>
-void GenerationCache<K, V>::attachToCache(const sp<Entry<K, V> >& entry) {
- if (!mYoungest.get()) {
- mYoungest = mOldest = entry;
- } else {
- entry->parent = mYoungest;
- mYoungest->child = entry;
- mYoungest = entry;
- }
-}
-
-template<typename K, typename V>
-void GenerationCache<K, V>::detachFromCache(const sp<Entry<K, V> >& entry) {
- if (entry->parent.get()) {
- entry->parent->child = entry->child;
- } else {
- mOldest = entry->child;
- }
-
- if (entry->child.get()) {
- entry->child->parent = entry->parent;
- } else {
- mYoungest = entry->parent;
- }
-
- entry->parent.clear();
- entry->child.clear();
-}
-
-}; // namespace android
-
-#endif // ANDROID_UTILS_GENERATION_CACHE_H
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