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-rw-r--r--ext/mixed/js/cache-map.js140
1 files changed, 0 insertions, 140 deletions
diff --git a/ext/mixed/js/cache-map.js b/ext/mixed/js/cache-map.js
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index c7d72e6b..00000000
--- a/ext/mixed/js/cache-map.js
+++ /dev/null
@@ -1,140 +0,0 @@
-/*
- * Copyright (C) 2020-2021 Yomichan Authors
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <https://www.gnu.org/licenses/>.
- */
-
-/**
- * Class which caches a map of values, keeping the most recently accessed values.
- */
-class CacheMap {
- /**
- * Creates a new CacheMap.
- * @param maxSize The maximum number of entries able to be stored in the cache.
- */
- constructor(maxSize) {
- if (!(
- typeof maxSize === 'number' &&
- Number.isFinite(maxSize) &&
- maxSize >= 0 &&
- Math.floor(maxSize) === maxSize
- )) {
- throw new Error('Invalid maxCount');
- }
-
- this._maxSize = maxSize;
- this._map = new Map();
- this._listFirst = this._createNode(null, null);
- this._listLast = this._createNode(null, null);
- this._resetEndNodes();
- }
-
- /**
- * Returns the number of items in the cache.
- */
- get size() {
- return this._map.size;
- }
-
- /**
- * Returns the maximum number of items that can be added to the cache.
- */
- get maxSize() {
- return this._maxSize;
- }
-
- /**
- * Returns whether or not an element exists at the given key.
- * @param key The key of the element.
- * @returns `true` if an element with the specified key exists, `false` otherwise.
- */
- has(key) {
- return this._map.has(key);
- }
-
- /**
- * Gets an element at the given key, if it exists. Otherwise, returns undefined.
- * @param key The key of the element.
- * @returns The existing value at the key, if any; `undefined` otherwise.
- */
- get(key) {
- const node = this._map.get(key);
- if (typeof node === 'undefined') { return void 0; }
- this._updateRecency(node);
- return node.value;
- }
-
- /**
- * Sets a value at a given key.
- * @param key The key of the element.
- * @param value The value to store in the cache.
- */
- set(key, value) {
- let node = this._map.get(key);
- if (typeof node !== 'undefined') {
- this._updateRecency(node);
- node.value = value;
- } else {
- if (this._maxSize <= 0) { return; }
-
- node = this._createNode(key, value);
- this._addNode(node, this._listFirst);
- this._map.set(key, node);
-
- // Remove
- for (let removeCount = this._map.size - this._maxSize; removeCount > 0; --removeCount) {
- node = this._listLast.previous;
- this._removeNode(node);
- this._map.delete(node.key);
- }
- }
- }
-
- /**
- * Clears the cache.
- */
- clear() {
- this._map.clear();
- this._resetEndNodes();
- }
-
- // Private
-
- _updateRecency(node) {
- this._removeNode(node);
- this._addNode(node, this._listFirst);
- }
-
- _createNode(key, value) {
- return {key, value, previous: null, next: null};
- }
-
- _addNode(node, previous) {
- const next = previous.next;
- node.next = next;
- node.previous = previous;
- previous.next = node;
- next.previous = node;
- }
-
- _removeNode(node) {
- node.next.previous = node.previous;
- node.previous.next = node.next;
- }
-
- _resetEndNodes() {
- this._listFirst.next = this._listLast;
- this._listLast.previous = this._listFirst;
- }
-}