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| author | Misko Hevery | 2012-03-23 14:03:24 -0700 |
|---|---|---|
| committer | Misko Hevery | 2012-03-28 11:16:35 -0700 |
| commit | 2430f52bb97fa9d682e5f028c977c5bf94c5ec38 (patch) | |
| tree | e7529b741d70199f36d52090b430510bad07f233 /src/ng/cacheFactory.js | |
| parent | 944098a4e0f753f06b40c73ca3e79991cec6c2e2 (diff) | |
| download | angular.js-2430f52bb97fa9d682e5f028c977c5bf94c5ec38.tar.bz2 | |
chore(module): move files around in preparation for more modules
Diffstat (limited to 'src/ng/cacheFactory.js')
| -rw-r--r-- | src/ng/cacheFactory.js | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/src/ng/cacheFactory.js b/src/ng/cacheFactory.js new file mode 100644 index 00000000..82c939cc --- /dev/null +++ b/src/ng/cacheFactory.js @@ -0,0 +1,159 @@ +/** + * @ngdoc object + * @name angular.module.ng.$cacheFactory + * + * @description + * Factory that constructs cache objects. + * + * + * @param {string} cacheId Name or id of the newly created cache. + * @param {object=} options Options object that specifies the cache behavior. Properties: + * + * - `{number=}` `capacity` — turns the cache into LRU cache. + * + * @returns {object} Newly created cache object with the following set of methods: + * + * - `{object}` `info()` — Returns id, size, and options of cache. + * - `{void}` `put({string} key, {*} value)` — Puts a new key-value pair into the cache. + * - `{{*}} `get({string} key) — Returns cached value for `key` or undefined for cache miss. + * - `{void}` `remove({string} key) — Removes a key-value pair from the cache. + * - `{void}` `removeAll() — Removes all cached values. + * - `{void}` `destroy() — Removes references to this cache from $cacheFactory. + * + */ +function $CacheFactoryProvider() { + + this.$get = function() { + var caches = {}; + + function cacheFactory(cacheId, options) { + if (cacheId in caches) { + throw Error('cacheId ' + cacheId + ' taken'); + } + + var size = 0, + stats = extend({}, options, {id: cacheId}), + data = {}, + capacity = (options && options.capacity) || Number.MAX_VALUE, + lruHash = {}, + freshEnd = null, + staleEnd = null; + + return caches[cacheId] = { + + put: function(key, value) { + var lruEntry = lruHash[key] || (lruHash[key] = {key: key}); + + refresh(lruEntry); + + if (isUndefined(value)) return; + if (!(key in data)) size++; + data[key] = value; + + if (size > capacity) { + this.remove(staleEnd.key); + } + }, + + + get: function(key) { + var lruEntry = lruHash[key]; + + if (!lruEntry) return; + + refresh(lruEntry); + + return data[key]; + }, + + + remove: function(key) { + var lruEntry = lruHash[key]; + + if (lruEntry == freshEnd) freshEnd = lruEntry.p; + if (lruEntry == staleEnd) staleEnd = lruEntry.n; + link(lruEntry.n,lruEntry.p); + + delete lruHash[key]; + delete data[key]; + size--; + }, + + + removeAll: function() { + data = {}; + size = 0; + lruHash = {}; + freshEnd = staleEnd = null; + }, + + + destroy: function() { + data = null; + stats = null; + lruHash = null; + delete caches[cacheId]; + }, + + + info: function() { + return extend({}, stats, {size: size}); + } + }; + + + /** + * makes the `entry` the freshEnd of the LRU linked list + */ + function refresh(entry) { + if (entry != freshEnd) { + if (!staleEnd) { + staleEnd = entry; + } else if (staleEnd == entry) { + staleEnd = entry.n; + } + + link(entry.n, entry.p); + link(entry, freshEnd); + freshEnd = entry; + freshEnd.n = null; + } + } + + + /** + * bidirectionally links two entries of the LRU linked list + */ + function link(nextEntry, prevEntry) { + if (nextEntry != prevEntry) { + if (nextEntry) nextEntry.p = prevEntry; //p stands for previous, 'prev' didn't minify + if (prevEntry) prevEntry.n = nextEntry; //n stands for next, 'next' didn't minify + } + } + } + + + cacheFactory.info = function() { + var info = {}; + forEach(caches, function(cache, cacheId) { + info[cacheId] = cache.info(); + }); + return info; + }; + + + cacheFactory.get = function(cacheId) { + return caches[cacheId]; + }; + + + return cacheFactory; + }; +} + +function $TemplateCacheProvider() { + this.$get = ['$cacheFactory', function($cacheFactory) { + return $cacheFactory('templates'); + }]; +} + |
