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Diffstat (limited to 'node_modules/montage-user/core/bitfield.js')
-rwxr-xr-x | node_modules/montage-user/core/bitfield.js | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/node_modules/montage-user/core/bitfield.js b/node_modules/montage-user/core/bitfield.js new file mode 100755 index 00000000..2c274d3c --- /dev/null +++ b/node_modules/montage-user/core/bitfield.js | |||
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1 | /* <copyright> | ||
2 | This file contains proprietary software owned by Motorola Mobility, Inc.<br/> | ||
3 | No rights, expressed or implied, whatsoever to this software are provided by Motorola Mobility, Inc. hereunder.<br/> | ||
4 | (c) Copyright 2011 Motorola Mobility, Inc. All Rights Reserved. | ||
5 | </copyright> */ | ||
6 | /** | ||
7 | Defines the BitField class, that compactly stores multiple values as a short series of bits. | ||
8 | @module montage/core/bitfield | ||
9 | @requires montage/core/core | ||
10 | */ | ||
11 | |||
12 | var Montage = require("montage").Montage; | ||
13 | |||
14 | |||
15 | /** | ||
16 | The BitField object compactly stores multiple values as a short series of bits. This implementation is limited to 32 fields. | ||
17 | @class module:montage/core/bitfield.BitField | ||
18 | @classdesc Compactly stores multiple values as a short series of bits. | ||
19 | @extends module:montage/core/core.Montage | ||
20 | */ | ||
21 | var BitField = exports.BitField = Montage.create(Montage, /** @lends module:montage/core/bitfield.BitField# */ { | ||
22 | |||
23 | /** | ||
24 | Creates a new BitField object containing the fields provided in the propertyDescriptor parameter. | ||
25 | @function | ||
26 | @param {Object} propertyDescriptor An object containing one or more property name/value pairs. Each pair is added to the new BitField. | ||
27 | @returns {Object} A new BitField object that contains fields described by the property descriptor. | ||
28 | @example var bitField = BitField.create(); | ||
29 | bitField = BitField.create().initWithDescriptor({ | ||
30 | likes_golf: { | ||
31 | value: false | ||
32 | }, | ||
33 | likes_basketball: { | ||
34 | value: true | ||
35 | }, | ||
36 | likes_baseball: { | ||
37 | value: false | ||
38 | }, | ||
39 | }); | ||
40 | */ | ||
41 | initWithDescriptor: { | ||
42 | enumerable: false, | ||
43 | value: function(propertyDescriptor) { | ||
44 | var fieldName; | ||
45 | this.reset(); | ||
46 | for (fieldName in propertyDescriptor) { | ||
47 | this.addField(fieldName, propertyDescriptor[fieldName].value); | ||
48 | } | ||
49 | return this; | ||
50 | } | ||
51 | }, | ||
52 | |||
53 | /** | ||
54 | Adds a new field to a BitField instance. | ||
55 | @function | ||
56 | @param {String} aFieldName The name of the field to add. | ||
57 | @param {Mixed} defaultValue The new field's default value. | ||
58 | */ | ||
59 | addField: { | ||
60 | enumerable: false, | ||
61 | value: function(aFieldName, defaultValue) { | ||
62 | if (aFieldName in this) { | ||
63 | return; | ||
64 | } | ||
65 | if (this._fieldCount >= 32) { | ||
66 | throw "BitField 32 fields limit reached."; | ||
67 | } | ||
68 | //We try to recycle slots as limited to 32bits | ||
69 | this._trueValue += (this._fields[aFieldName] = this._constantsToReuse.length ? this._constantsToReuse.shift() : (1 << this._fieldCount)); | ||
70 | Montage.defineProperty(this, aFieldName, { | ||
71 | enumerable: true, | ||
72 | get: function() { | ||
73 | return (this._value === this._trueValue); | ||
74 | }, | ||
75 | set: function(value) { | ||
76 | value ? (this._value |= this._fields[aFieldName]) : (this._value &= ~ (this._fields[aFieldName])); | ||
77 | if (this.value) { | ||
78 | this.callDelegateMethod(); | ||
79 | } | ||
80 | } | ||
81 | }); | ||
82 | this._fieldCount++; | ||
83 | if (!! defaultValue) { | ||
84 | this[aFieldName] = true; | ||
85 | } | ||
86 | } | ||
87 | }, | ||
88 | |||
89 | /** | ||
90 | @private | ||
91 | */ | ||
92 | _constantsToReuse: { | ||
93 | enumerable: false, | ||
94 | value: [] | ||
95 | }, | ||
96 | |||
97 | /** | ||
98 | Removes a field from the bitfield. | ||
99 | @function | ||
100 | @param {String} aFieldName The name of the field to remove. | ||
101 | */ | ||
102 | removeField: { | ||
103 | enumerable: false, | ||
104 | value: function(aFieldName) { | ||
105 | delete this[aFieldName]; | ||
106 | this._constantsToReuse.push(this._fields[aFieldName]); | ||
107 | this._trueValue -= this._fields[aFieldName]; | ||
108 | delete this._fields[aFieldName]; | ||
109 | } | ||
110 | }, | ||
111 | |||
112 | /** | ||
113 | The BitField object's delegate. | ||
114 | @type {Property} | ||
115 | @default null | ||
116 | */ | ||
117 | delegate: { | ||
118 | enumerable: false, | ||
119 | value: null | ||
120 | }, | ||
121 | |||
122 | /** | ||
123 | @function | ||
124 | @returns Nothing | ||
125 | */ | ||
126 | callDelegateMethod: { | ||
127 | value: function() { | ||
128 | var delegateMethod; | ||
129 | if (this.delegate && typeof (delegateMethod = this.delegate.bitFieldDidBecomeTrue) === "function") { | ||
130 | delegateMethod.call(this.delegate, this); | ||
131 | } | ||
132 | }, | ||
133 | enumerable: false | ||
134 | }, | ||
135 | /** | ||
136 | @type {Function} | ||
137 | @default {Number} 0 | ||
138 | */ | ||
139 | value: { | ||
140 | enumerable: false, | ||
141 | get: function() { | ||
142 | return (this._value === this._trueValue); | ||
143 | } | ||
144 | }, | ||
145 | |||
146 | /** | ||
147 | @private | ||
148 | */ | ||
149 | _fieldCount: { | ||
150 | enumerable: false, | ||
151 | value: 0 | ||
152 | }, | ||
153 | /** | ||
154 | @private | ||
155 | */ | ||
156 | _value: { | ||
157 | enumerable: false, | ||
158 | value: 0 | ||
159 | }, | ||
160 | /** | ||
161 | @private | ||
162 | */ | ||
163 | _trueValue: { | ||
164 | enumerable: false, | ||
165 | value: 0 | ||
166 | }, | ||
167 | /** | ||
168 | @function | ||
169 | */ | ||
170 | reset: { | ||
171 | enumerable: false, | ||
172 | value: function() { | ||
173 | this._value = 0x0; | ||
174 | } | ||
175 | }, | ||
176 | /** | ||
177 | @private | ||
178 | */ | ||
179 | _fields: { | ||
180 | enumerable: false, | ||
181 | value: {} | ||
182 | }, | ||
183 | /** | ||
184 | @function | ||
185 | @returns result | ||
186 | */ | ||
187 | toString: { | ||
188 | value: function() { | ||
189 | var fieldNames = this._fields, | ||
190 | i, | ||
191 | iField, | ||
192 | result = ""; | ||
193 | for (i = 0; (iField = fieldNames[i]); i++) { | ||
194 | result += iField + "[" + (this._value & fieldNames[iField]) + "], "; | ||
195 | } | ||
196 | return result; | ||
197 | } | ||
198 | } | ||
199 | }); | ||