| // Copyright 2011 The Closure Library Authors. All Rights Reserved. |
| // |
| // 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. |
| |
| /** |
| * @fileoverview Wraps an iterable storage mechanism and creates artificial |
| * namespaces using a prefix in the global namespace. |
| * |
| */ |
| |
| goog.provide('goog.storage.mechanism.PrefixedMechanism'); |
| |
| goog.require('goog.iter.Iterator'); |
| goog.require('goog.storage.mechanism.IterableMechanism'); |
| |
| |
| |
| /** |
| * Wraps an iterable storage mechanism and creates artificial namespaces. |
| * |
| * @param {!goog.storage.mechanism.IterableMechanism} mechanism Underlying |
| * iterable storage mechanism. |
| * @param {string} prefix Prefix for creating an artificial namespace. |
| * @constructor |
| * @extends {goog.storage.mechanism.IterableMechanism} |
| * @final |
| */ |
| goog.storage.mechanism.PrefixedMechanism = function(mechanism, prefix) { |
| goog.storage.mechanism.PrefixedMechanism.base(this, 'constructor'); |
| this.mechanism_ = mechanism; |
| this.prefix_ = prefix + '::'; |
| }; |
| goog.inherits(goog.storage.mechanism.PrefixedMechanism, |
| goog.storage.mechanism.IterableMechanism); |
| |
| |
| /** |
| * The mechanism to be prefixed. |
| * |
| * @type {goog.storage.mechanism.IterableMechanism} |
| * @private |
| */ |
| goog.storage.mechanism.PrefixedMechanism.prototype.mechanism_ = null; |
| |
| |
| /** |
| * The prefix for creating artificial namespaces. |
| * |
| * @type {string} |
| * @private |
| */ |
| goog.storage.mechanism.PrefixedMechanism.prototype.prefix_ = ''; |
| |
| |
| /** @override */ |
| goog.storage.mechanism.PrefixedMechanism.prototype.set = function(key, value) { |
| this.mechanism_.set(this.prefix_ + key, value); |
| }; |
| |
| |
| /** @override */ |
| goog.storage.mechanism.PrefixedMechanism.prototype.get = function(key) { |
| return this.mechanism_.get(this.prefix_ + key); |
| }; |
| |
| |
| /** @override */ |
| goog.storage.mechanism.PrefixedMechanism.prototype.remove = function(key) { |
| this.mechanism_.remove(this.prefix_ + key); |
| }; |
| |
| |
| /** @override */ |
| goog.storage.mechanism.PrefixedMechanism.prototype.__iterator__ = function( |
| opt_keys) { |
| var subIter = this.mechanism_.__iterator__(true); |
| var selfObj = this; |
| var newIter = new goog.iter.Iterator(); |
| newIter.next = function() { |
| var key = /** @type {string} */ (subIter.next()); |
| while (key.substr(0, selfObj.prefix_.length) != selfObj.prefix_) { |
| key = /** @type {string} */ (subIter.next()); |
| } |
| return opt_keys ? key.substr(selfObj.prefix_.length) : |
| selfObj.mechanism_.get(key); |
| }; |
| return newIter; |
| }; |