1 | // Copyright 2010 The Closure Library Authors. All Rights Reserved. |
2 | // |
3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
4 | // you may not use this file except in compliance with the License. |
5 | // You may obtain a copy of the License at |
6 | // |
7 | // http://www.apache.org/licenses/LICENSE-2.0 |
8 | // |
9 | // Unless required by applicable law or agreed to in writing, software |
10 | // distributed under the License is distributed on an "AS-IS" BASIS, |
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
12 | // See the License for the specific language governing permissions and |
13 | // limitations under the License. |
14 | |
15 | /** |
16 | * @fileoverview Interface for a factory for creating XMLHttpRequest objects |
17 | * and metadata about them. |
18 | * @author dbk@google.com (David Barrett-Kahn) |
19 | */ |
20 | |
21 | goog.provide('goog.net.XmlHttpFactory'); |
22 | |
23 | |
24 | |
25 | /** |
26 | * Abstract base class for an XmlHttpRequest factory. |
27 | * @constructor |
28 | */ |
29 | goog.net.XmlHttpFactory = function() { |
30 | }; |
31 | |
32 | |
33 | /** |
34 | * Cache of options - we only actually call internalGetOptions once. |
35 | * @type {Object} |
36 | * @private |
37 | */ |
38 | goog.net.XmlHttpFactory.prototype.cachedOptions_ = null; |
39 | |
40 | |
41 | /** |
42 | * @return {!(XMLHttpRequest|GearsHttpRequest)} A new XMLHttpRequest instance. |
43 | */ |
44 | goog.net.XmlHttpFactory.prototype.createInstance = goog.abstractMethod; |
45 | |
46 | |
47 | /** |
48 | * @return {Object} Options describing how xhr objects obtained from this |
49 | * factory should be used. |
50 | */ |
51 | goog.net.XmlHttpFactory.prototype.getOptions = function() { |
52 | return this.cachedOptions_ || |
53 | (this.cachedOptions_ = this.internalGetOptions()); |
54 | }; |
55 | |
56 | |
57 | /** |
58 | * Override this method in subclasses to preserve the caching offered by |
59 | * getOptions(). |
60 | * @return {Object} Options describing how xhr objects obtained from this |
61 | * factory should be used. |
62 | * @protected |
63 | */ |
64 | goog.net.XmlHttpFactory.prototype.internalGetOptions = goog.abstractMethod; |