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:
| 1 | <?php  | 
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| 36 | class TicketExtension extends DataExtension  | 
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| 37 | { | 
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| 38 | /**  | 
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| 39 | * @var CalendarEvent_Controller  | 
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| 40 | */  | 
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| 41 | protected $controller;  | 
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| 42 | |||
| 43 | private static $db = array(  | 
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| 44 | 'Capacity' => 'Int',  | 
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| 45 | 'SuccessMessage' => 'HTMLText',  | 
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| 46 | 'SuccessMessageMail' => 'HTMLText'  | 
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| 47 | );  | 
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| 48 | |||
| 49 | private static $has_many = array(  | 
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| 50 | 'Tickets' => 'Broarm\EventTickets\Ticket.Event',  | 
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| 51 | 'Reservations' => 'Broarm\EventTickets\Reservation.Event',  | 
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| 52 | 'Attendees' => 'Broarm\EventTickets\Attendee.Event'  | 
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| 53 | );  | 
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| 54 | |||
| 55 | public function updateCMSFields(FieldList $fields)  | 
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| 56 |     { | 
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| 57 | $gridFieldConfig = GridFieldConfig_RecordEditor::create();  | 
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| 58 | |||
| 59 | // If the event dates are in the past remove ability to create new tickets, reservations and attendees.  | 
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| 60 | // This is done here instead of in the canCreate method because of the lack of context there.  | 
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| 61 |         if (!$this->canCreateTickets()) { | 
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| 62 | $gridFieldConfig->removeComponentsByType(new GridFieldAddNewButton());  | 
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| 63 | }  | 
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| 64 | |||
| 65 |         $ticketLabel = _t('TicketExtension.Tickets', 'Tickets'); | 
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| 66 | $fields->addFieldsToTab(  | 
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| 67 | "Root.$ticketLabel", array(  | 
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| 68 |             GridField::create('Tickets', $ticketLabel, $this->owner->Tickets(), $gridFieldConfig), | 
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| 69 |             NumericField::create('Capacity', _t('TicketExtension.Capacity', 'Capacity')), | 
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| 70 |             HtmlEditorField::create('SuccessMessage', 'Success message')->setRows(4), | 
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| 71 |             HtmlEditorField::create('SuccessMessageMail', 'Mail message')->setRows(4) | 
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| 72 | ));  | 
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| 73 | |||
| 74 |         if ($this->owner->Reservations()->exists()) { | 
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| 75 |             $reservationLabel = _t('TicketExtension.Reservations', 'Reservations'); | 
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| 76 | $fields->addFieldToTab(  | 
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| 77 | "Root.$reservationLabel",  | 
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| 78 |                 GridField::create('Reservations', $reservationLabel, $this->owner->Reservations(), $gridFieldConfig) | 
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| 79 | );  | 
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| 80 | }  | 
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| 81 | |||
| 82 |         if ($this->owner->Attendees()->exists()) { | 
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| 83 |             $guestListLabel = _t('TicketExtension.GuestList', 'GuestList'); | 
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| 84 | $fields->addFieldToTab(  | 
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| 85 | "Root.$guestListLabel",  | 
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| 86 |                 GridField::create('Attendees', $guestListLabel, $this->owner->Attendees(), $gridFieldConfig) | 
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| 87 | );  | 
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| 88 | }  | 
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| 89 | |||
| 90 | return $fields;  | 
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| 91 | }  | 
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| 92 | |||
| 93 | /**  | 
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| 94 | * Extend the page actions with an start check in action  | 
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| 95 | *  | 
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| 96 | * @param FieldList $actions  | 
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| 97 | */  | 
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| 98 | public function updateCMSActions(FieldList $actions)  | 
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| 114 | |||
| 115 | /**  | 
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| 116 | * Get the leftover capacity  | 
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| 117 | *  | 
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| 118 | * @return int  | 
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| 119 | */  | 
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| 120 | public function getAvailability()  | 
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| 124 | |||
| 125 | /**  | 
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| 126 | * Get the success message  | 
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| 127 | *  | 
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| 128 | * @return mixed|string  | 
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| 129 | */  | 
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| 130 | View Code Duplication | public function getSuccessContent()  | 
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| 138 | |||
| 139 | /**  | 
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| 140 | * Get the mail message  | 
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| 141 | *  | 
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| 142 | * @return mixed|string  | 
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| 143 | */  | 
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| 144 | View Code Duplication | public function getMailContent()  | 
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| 152 | |||
| 153 | /**  | 
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| 154 | * Get the Ticket logo  | 
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| 155 | *  | 
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| 156 | * @return \Image  | 
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| 157 | */  | 
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| 158 | public function getMailLogo()  | 
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| 162 | |||
| 163 | /**  | 
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| 164 | * Check if the current event can have tickets  | 
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| 165 | *  | 
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| 166 | * @return bool  | 
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| 167 | */  | 
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| 168 | public function canCreateTickets()  | 
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| 177 | |||
| 178 | /**  | 
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| 179 | * Get the calendar controller  | 
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| 180 | *  | 
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| 181 | * @return CalendarEvent_Controller  | 
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| 182 | */  | 
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| 183 | public function getController()  | 
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| 189 | }  | 
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| 190 | 
This check marks private properties in classes that are never used. Those properties can be removed.