Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like Event often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Event, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 30 | class Event extends Component  | 
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| 31 | { | 
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| 32 | const TIME_TRANSPARENCY_OPAQUE = 'OPAQUE';  | 
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| 33 | const TIME_TRANSPARENCY_TRANSPARENT = 'TRANSPARENT';  | 
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| 34 | |||
| 35 | const STATUS_TENTATIVE = 'TENTATIVE';  | 
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| 36 | const STATUS_CONFIRMED = 'CONFIRMED';  | 
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| 37 | const STATUS_CANCELLED = 'CANCELLED';  | 
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| 38 | |||
| 39 | /**  | 
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| 40 | * @var string  | 
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| 41 | */  | 
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| 42 | protected $uniqueId;  | 
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| 43 | |||
| 44 | /**  | 
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| 45 | * The property indicates the date/time that the instance of  | 
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| 46 | * the iCalendar object was created.  | 
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| 47 | *  | 
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| 48 | * The value MUST be specified in the UTC time format.  | 
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| 49 | *  | 
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| 50 | * @var \DateTime  | 
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| 51 | */  | 
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| 52 | protected $dtStamp;  | 
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| 53 | |||
| 54 | /**  | 
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| 55 | * @var \DateTime  | 
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| 56 | */  | 
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| 57 | protected $dtStart;  | 
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| 58 | |||
| 59 | /**  | 
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| 60 | * Preferentially chosen over the duration if both are set.  | 
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| 61 | *  | 
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| 62 | * @var \DateTime  | 
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| 63 | */  | 
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| 64 | protected $dtEnd;  | 
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| 65 | |||
| 66 | /**  | 
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| 67 | * @var \DateInterval  | 
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| 68 | */  | 
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| 69 | protected $duration;  | 
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| 70 | |||
| 71 | /**  | 
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| 72 | * @var bool  | 
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| 73 | */  | 
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| 74 | protected $noTime = false;  | 
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| 75 | |||
| 76 | /**  | 
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| 77 | * @var string  | 
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| 78 | */  | 
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| 79 | protected $url;  | 
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| 80 | |||
| 81 | /**  | 
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| 82 | * @var string  | 
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| 83 | */  | 
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| 84 | protected $location;  | 
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| 85 | |||
| 86 | /**  | 
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| 87 | * @var string  | 
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| 88 | */  | 
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| 89 | protected $locationTitle;  | 
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| 90 | |||
| 91 | /**  | 
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| 92 | * @var Geo  | 
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| 93 | */  | 
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| 94 | protected $locationGeo;  | 
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| 95 | |||
| 96 | /**  | 
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| 97 | * @var string  | 
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| 98 | */  | 
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| 99 | protected $summary;  | 
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| 100 | |||
| 101 | /**  | 
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| 102 | * @var Organizer  | 
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| 103 | */  | 
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| 104 | protected $organizer;  | 
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| 105 | |||
| 106 | /**  | 
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| 107 | * @see https://tools.ietf.org/html/rfc5545#section-3.8.2.7  | 
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| 108 | *  | 
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| 109 | * @var string  | 
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| 110 | */  | 
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| 111 | protected $transparency = self::TIME_TRANSPARENCY_OPAQUE;  | 
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| 112 | |||
| 113 | /**  | 
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| 114 | * If set to true the timezone will be added to the event.  | 
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| 115 | *  | 
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| 116 | * @var bool  | 
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| 117 | */  | 
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| 118 | protected $useTimezone = false;  | 
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| 119 | |||
| 120 | /**  | 
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| 121 | * If set will we used as the timezone identifier.  | 
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| 122 | *  | 
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| 123 | * @var string  | 
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| 124 | */  | 
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| 125 | protected $timezoneString = '';  | 
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| 126 | |||
| 127 | /**  | 
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| 128 | * @var int  | 
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| 129 | */  | 
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| 130 | protected $sequence = 0;  | 
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| 131 | |||
| 132 | /**  | 
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| 133 | * @var Attendees  | 
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| 134 | */  | 
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| 135 | protected $attendees;  | 
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| 136 | |||
| 137 | /**  | 
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| 138 | * @var string  | 
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| 139 | */  | 
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| 140 | protected $description;  | 
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| 141 | |||
| 142 | /**  | 
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| 143 | * @var string  | 
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| 144 | */  | 
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| 145 | protected $descriptionHTML;  | 
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| 146 | |||
| 147 | /**  | 
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| 148 | * @var string  | 
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| 149 | */  | 
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| 150 | protected $status;  | 
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| 151 | |||
| 152 | /**  | 
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| 153 | * @var RecurrenceRule  | 
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| 154 | */  | 
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| 155 | protected $recurrenceRule;  | 
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| 156 | |||
| 157 | /**  | 
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| 158 | * @var array  | 
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| 159 | */  | 
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| 160 | protected $recurrenceRules = [];  | 
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| 161 | |||
| 162 | /**  | 
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| 163 | * This property specifies the date and time that the calendar  | 
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| 164 | * information was created.  | 
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| 165 | *  | 
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| 166 | * The value MUST be specified in the UTC time format.  | 
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| 167 | *  | 
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| 168 | * @var \DateTime  | 
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| 169 | */  | 
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| 170 | protected $created;  | 
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| 171 | |||
| 172 | /**  | 
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| 173 | * The property specifies the date and time that the information  | 
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| 174 | * associated with the calendar component was last revised.  | 
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| 175 | *  | 
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| 176 | * The value MUST be specified in the UTC time format.  | 
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| 177 | *  | 
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| 178 | * @var \DateTime  | 
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| 179 | */  | 
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| 180 | protected $modified;  | 
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| 181 | |||
| 182 | /**  | 
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| 183 | * Indicates if the UTC time should be used or not.  | 
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| 184 | *  | 
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| 185 | * @var bool  | 
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| 186 | */  | 
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| 187 | protected $useUtc = true;  | 
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| 188 | |||
| 189 | /**  | 
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| 190 | * @var bool  | 
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| 191 | */  | 
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| 192 | protected $cancelled;  | 
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| 193 | |||
| 194 | /**  | 
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| 195 | * This property is used to specify categories or subtypes  | 
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| 196 | * of the calendar component. The categories are useful in searching  | 
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| 197 | * for a calendar component of a particular type and category.  | 
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| 198 | *  | 
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| 199 | * @see https://tools.ietf.org/html/rfc5545#section-3.8.1.2  | 
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| 200 | *  | 
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| 201 | * @var array  | 
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| 202 | */  | 
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| 203 | protected $categories;  | 
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| 204 | |||
| 205 | /**  | 
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| 206 | * https://tools.ietf.org/html/rfc5545#section-3.8.1.3.  | 
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| 207 | *  | 
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| 208 | * @var bool  | 
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| 209 | */  | 
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| 210 | protected $isPrivate = false;  | 
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| 211 | |||
| 212 | /**  | 
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| 213 | * Dates to be excluded from a series of events.  | 
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| 214 | *  | 
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| 215 | * @var \DateTimeInterface[]  | 
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| 216 | */  | 
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| 217 | protected $exDates = [];  | 
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| 218 | |||
| 219 | /**  | 
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| 220 | * @var RecurrenceId  | 
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| 221 | */  | 
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| 222 | protected $recurrenceId;  | 
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| 223 | |||
| 224 | /**  | 
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| 225 | * @var Attachment[]  | 
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| 226 | */  | 
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| 227 | protected $attachments = [];  | 
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| 228 | |||
| 229 | 26 | public function __construct(string $uniqueId = null)  | 
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| 238 | |||
| 239 | /**  | 
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| 240 |      * {@inheritdoc} | 
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| 241 | */  | 
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| 242 | 7 | public function getType()  | 
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| 246 | |||
| 247 | /**  | 
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| 248 |      * {@inheritdoc} | 
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| 249 | */  | 
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| 250 | 17 | public function buildPropertyBag()  | 
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| 381 | |||
| 382 | /**  | 
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| 383 | * @param $dtEnd  | 
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| 384 | *  | 
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| 385 | * @return $this  | 
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| 386 | */  | 
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| 387 | 5 | public function setDtEnd($dtEnd)  | 
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| 393 | |||
| 394 | 2 | public function getDtEnd()  | 
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| 398 | |||
| 399 | 5 | public function setDtStart($dtStart)  | 
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| 405 | |||
| 406 | 2 | public function getDtStart()  | 
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| 410 | |||
| 411 | /**  | 
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| 412 | * @param $dtStamp  | 
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| 413 | *  | 
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| 414 | * @return $this  | 
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| 415 | */  | 
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| 416 | 1 | public function setDtStamp($dtStamp)  | 
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| 422 | |||
| 423 | /**  | 
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| 424 | * @param $duration  | 
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| 425 | *  | 
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| 426 | * @return $this  | 
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| 427 | */  | 
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| 428 | 1 | public function setDuration($duration)  | 
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| 434 | |||
| 435 | /**  | 
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| 436 | * @param string $location  | 
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| 437 | * @param string $title  | 
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| 438 | * @param Geo|string $geo  | 
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| 439 | *  | 
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| 440 | * @return $this  | 
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| 441 | */  | 
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| 442 | 3 | public function setLocation($location, $title = '', $geo = null)  | 
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| 460 | |||
| 461 | /**  | 
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| 462 | * @param Geo $geoProperty  | 
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| 463 | *  | 
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| 464 | * @return $this  | 
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| 465 | */  | 
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| 466 | 1 | public function setGeoLocation(Geo $geoProperty)  | 
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| 472 | |||
| 473 | /**  | 
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| 474 | * @param $noTime  | 
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| 475 | *  | 
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| 476 | * @return $this  | 
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| 477 | */  | 
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| 478 | 1 | public function setNoTime($noTime)  | 
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| 484 | |||
| 485 | /**  | 
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| 486 | * @param int $sequence  | 
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| 487 | *  | 
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| 488 | * @return $this  | 
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| 489 | */  | 
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| 490 | 2 | public function setSequence($sequence)  | 
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| 496 | |||
| 497 | /**  | 
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| 498 | * @return int  | 
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| 499 | */  | 
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| 500 | 1 | public function getSequence()  | 
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| 504 | |||
| 505 | /**  | 
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| 506 | * @param Organizer $organizer  | 
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| 507 | *  | 
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| 508 | * @return $this  | 
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| 509 | */  | 
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| 510 | 2 | public function setOrganizer(Organizer $organizer)  | 
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| 516 | |||
| 517 | /**  | 
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| 518 | * @param $summary  | 
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| 519 | *  | 
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| 520 | * @return $this  | 
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| 521 | */  | 
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| 522 | 1 | public function setSummary($summary)  | 
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| 528 | |||
| 529 | /**  | 
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| 530 | * @param $uniqueId  | 
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| 531 | *  | 
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| 532 | * @return $this  | 
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| 533 | */  | 
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| 534 | 1 | public function setUniqueId($uniqueId)  | 
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| 540 | |||
| 541 | /**  | 
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| 542 | * @return string  | 
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| 543 | */  | 
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| 544 | 2 | public function getUniqueId()  | 
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| 548 | |||
| 549 | /**  | 
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| 550 | * @param $url  | 
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| 551 | *  | 
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| 552 | * @return $this  | 
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| 553 | */  | 
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| 554 | 1 | public function setUrl($url)  | 
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| 560 | |||
| 561 | /**  | 
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| 562 | * @param $useTimezone  | 
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| 563 | *  | 
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| 564 | * @return $this  | 
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| 565 | */  | 
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| 566 | public function setUseTimezone($useTimezone)  | 
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| 572 | |||
| 573 | /**  | 
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| 574 | * @return bool  | 
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| 575 | */  | 
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| 576 | public function getUseTimezone()  | 
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| 580 | |||
| 581 | /**  | 
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| 582 | * @param $timezoneString  | 
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| 583 | *  | 
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| 584 | * @return $this  | 
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| 585 | */  | 
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| 586 | 2 | public function setTimezoneString($timezoneString)  | 
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| 592 | |||
| 593 | /**  | 
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| 594 | * @return bool  | 
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| 595 | */  | 
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| 596 | 1 | public function getTimezoneString()  | 
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| 600 | |||
| 601 | /**  | 
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| 602 | * @param Attendees $attendees  | 
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| 603 | *  | 
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| 604 | * @return $this  | 
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| 605 | */  | 
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| 606 | public function setAttendees(Attendees $attendees)  | 
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| 612 | |||
| 613 | /**  | 
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| 614 | * @param string $attendee  | 
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| 615 | * @param array $params  | 
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| 616 | *  | 
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| 617 | * @return $this  | 
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| 618 | */  | 
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| 619 | public function addAttendee($attendee, $params = [])  | 
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| 625 | |||
| 626 | /**  | 
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| 627 | * @return Attendees  | 
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| 628 | */  | 
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| 629 | public function getAttendees(): Attendees  | 
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| 633 | |||
| 634 | /**  | 
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| 635 | * @param $description  | 
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| 636 | *  | 
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| 637 | * @return $this  | 
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| 638 | */  | 
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| 639 | 4 | public function setDescription($description)  | 
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| 645 | |||
| 646 | /**  | 
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| 647 | * @param $descriptionHTML  | 
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| 648 | *  | 
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| 649 | * @return $this  | 
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| 650 | */  | 
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| 651 | public function setDescriptionHTML($descriptionHTML)  | 
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| 657 | |||
| 658 | /**  | 
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| 659 | * @param bool $useUtc  | 
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| 660 | *  | 
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| 661 | * @return $this  | 
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| 662 | */  | 
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| 663 | public function setUseUtc($useUtc = true)  | 
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| 669 | |||
| 670 | /**  | 
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| 671 | * @return string  | 
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| 672 | */  | 
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| 673 | public function getDescription()  | 
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| 677 | |||
| 678 | /**  | 
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| 679 | * @return string  | 
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| 680 | */  | 
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| 681 | public function getDescriptionHTML()  | 
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| 685 | |||
| 686 | /**  | 
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| 687 | * @param $status  | 
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| 688 | *  | 
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| 689 | * @return $this  | 
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| 690 | */  | 
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| 691 | public function setCancelled($status)  | 
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| 697 | |||
| 698 | /**  | 
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| 699 | * @param $transparency  | 
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| 700 | *  | 
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| 701 | * @return $this  | 
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| 702 | *  | 
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| 703 | * @throws \InvalidArgumentException  | 
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| 704 | */  | 
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| 705 | View Code Duplication | public function setTimeTransparency($transparency)  | 
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| 718 | |||
| 719 | /**  | 
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| 720 | * @param $status  | 
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| 721 | *  | 
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| 722 | * @return $this  | 
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| 723 | *  | 
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| 724 | * @throws \InvalidArgumentException  | 
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| 725 | */  | 
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| 726 | public function setStatus($status)  | 
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| 740 | |||
| 741 | /**  | 
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| 742 | * @deprecated Deprecated since version 0.11.0, to be removed in 1.0. Use addRecurrenceRule instead.  | 
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| 743 | *  | 
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| 744 | * @param RecurrenceRule $recurrenceRule  | 
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| 745 | *  | 
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| 746 | * @return $this  | 
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| 747 | */  | 
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| 748 | public function setRecurrenceRule(RecurrenceRule $recurrenceRule)  | 
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| 756 | |||
| 757 | /**  | 
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| 758 | * @deprecated Deprecated since version 0.11.0, to be removed in 1.0. Use getRecurrenceRules instead.  | 
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| 759 | *  | 
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| 760 | * @return RecurrenceRule  | 
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| 761 | */  | 
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| 762 | public function getRecurrenceRule()  | 
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| 768 | |||
| 769 | /**  | 
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| 770 | * @param RecurrenceRule $recurrenceRule  | 
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| 771 | *  | 
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| 772 | * @return $this  | 
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| 773 | */  | 
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| 774 | public function addRecurrenceRule(RecurrenceRule $recurrenceRule)  | 
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| 780 | |||
| 781 | /**  | 
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| 782 | * @return array  | 
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| 783 | */  | 
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| 784 | public function getRecurrenceRules()  | 
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| 788 | |||
| 789 | /**  | 
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| 790 | * @param $dtStamp  | 
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| 791 | *  | 
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| 792 | * @return $this  | 
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| 793 | */  | 
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| 794 | public function setCreated($dtStamp)  | 
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| 800 | |||
| 801 | /**  | 
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| 802 | * @param $dtStamp  | 
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| 803 | *  | 
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| 804 | * @return $this  | 
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| 805 | */  | 
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| 806 | public function setModified($dtStamp)  | 
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| 812 | |||
| 813 | /**  | 
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| 814 | * @param $categories  | 
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| 815 | *  | 
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| 816 | * @return $this  | 
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| 817 | */  | 
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| 818 | public function setCategories($categories)  | 
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| 824 | |||
| 825 | /**  | 
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| 826 | * Sets the event privacy.  | 
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| 827 | *  | 
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| 828 | * @param bool $flag  | 
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| 829 | *  | 
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| 830 | * @return $this  | 
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| 831 | */  | 
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| 832 | public function setIsPrivate($flag)  | 
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| 838 | |||
| 839 | /**  | 
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| 840 | * @param \DateTimeInterface $dateTime  | 
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| 841 | *  | 
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| 842 | * @return \Eluceo\iCal\Component\Event  | 
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| 843 | */  | 
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| 844 | public function addExDate(\DateTimeInterface $dateTime)  | 
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| 850 | |||
| 851 | /**  | 
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| 852 | * @return \DateTimeInterface[]  | 
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| 853 | */  | 
            ||
| 854 | public function getExDates()  | 
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| 858 | |||
| 859 | /**  | 
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| 860 | * @param \DateTimeInterface[]  | 
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| 861 | *  | 
            ||
| 862 | * @return \Eluceo\iCal\Component\Event  | 
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| 863 | */  | 
            ||
| 864 | public function setExDates(array $exDates)  | 
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| 870 | |||
| 871 | /**  | 
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| 872 | * @return \Eluceo\iCal\Property\Event\RecurrenceId  | 
            ||
| 873 | */  | 
            ||
| 874 | public function getRecurrenceId()  | 
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| 878 | |||
| 879 | /**  | 
            ||
| 880 | * @param RecurrenceId $recurrenceId  | 
            ||
| 881 | *  | 
            ||
| 882 | * @return \Eluceo\iCal\Component\Event  | 
            ||
| 883 | */  | 
            ||
| 884 | public function setRecurrenceId(RecurrenceId $recurrenceId)  | 
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| 890 | |||
| 891 | /**  | 
            ||
| 892 | * @param array $attachment  | 
            ||
| 893 | *  | 
            ||
| 894 | * @return $this  | 
            ||
| 895 | */  | 
            ||
| 896 | 1 | public function addAttachment(Attachment $attachment)  | 
            |
| 897 |     { | 
            ||
| 898 | 1 | $this->attachments[] = $attachment;  | 
            |
| 899 | |||
| 900 | 1 | return $this;  | 
            |
| 901 | }  | 
            ||
| 902 | |||
| 903 | /**  | 
            ||
| 904 | * @return array  | 
            ||
| 905 | */  | 
            ||
| 906 | public function getAttachments()  | 
            ||
| 910 | |||
| 911 | /**  | 
            ||
| 912 | * @param string $url  | 
            ||
| 913 | */  | 
            ||
| 914 | public function addUrlAttachment(string $url)  | 
            ||
| 918 | }  | 
            ||
| 919 |