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  | 
            ||
| 5 | class ImagesWithStyleSelection extends DataObject  | 
            ||
| 
                                                                                                    
                        
                         | 
                |||
| 6 | { | 
            ||
| 7 | |||
| 8 | |||
| 9 | #######################  | 
            ||
| 10 | ### Names Section  | 
            ||
| 11 | #######################  | 
            ||
| 12 | |||
| 13 | private static $singular_name = 'Selection of Images';  | 
            ||
| 14 | |||
| 15 | public function i18n_singular_name()  | 
            ||
| 19 | |||
| 20 | private static $plural_name = 'Selections of Images';  | 
            ||
| 21 | |||
| 22 | public function i18n_plural_name()  | 
            ||
| 26 | |||
| 27 | |||
| 28 | #######################  | 
            ||
| 29 | ### Model Section  | 
            ||
| 30 | #######################  | 
            ||
| 31 | |||
| 32 | private static $db = [  | 
            ||
| 33 | 'Title' => 'Varchar(255)', // this needs to be lengthy to avoid the same names ...  | 
            ||
| 34 | 'Description' => 'Text'  | 
            ||
| 35 | ];  | 
            ||
| 36 | |||
| 37 | private static $has_one = [  | 
            ||
| 38 | 'PlaceToStoreImages' => 'Folder'  | 
            ||
| 39 | ];  | 
            ||
| 40 | |||
| 41 | private static $many_many = [  | 
            ||
| 42 | 'StyledImages' => 'ImageWithStyle'  | 
            ||
| 43 | ];  | 
            ||
| 44 | |||
| 45 | private static $many_many_extraFields = [  | 
            ||
| 46 | 'StyledImages' => [  | 
            ||
| 47 | 'SortOrder' => 'Int',  | 
            ||
| 48 | ]  | 
            ||
| 49 | ];  | 
            ||
| 50 | |||
| 51 | |||
| 52 | |||
| 53 | #######################  | 
            ||
| 54 | ### Further DB Field Details  | 
            ||
| 55 | #######################  | 
            ||
| 56 | |||
| 57 | private static $indexes = [  | 
            ||
| 58 | 'Created' => true,  | 
            ||
| 59 |         'Title' => 'unique("Title")' | 
            ||
| 60 | ];  | 
            ||
| 61 | |||
| 62 | private static $defaults = [  | 
            ||
| 63 | 'Title' => ''  | 
            ||
| 64 | ];  | 
            ||
| 65 | |||
| 66 | private static $default_sort = [  | 
            ||
| 67 | 'Created' => 'DESC'  | 
            ||
| 68 | ];  | 
            ||
| 69 | |||
| 70 | private static $required_fields = [  | 
            ||
| 71 | 'Title'  | 
            ||
| 72 | ];  | 
            ||
| 73 | |||
| 74 | private static $searchable_fields = [  | 
            ||
| 75 | 'Title' => 'PartialMatchFilter'  | 
            ||
| 76 | ];  | 
            ||
| 77 | |||
| 78 | |||
| 79 | #######################  | 
            ||
| 80 | ### Field Names and Presentation Section  | 
            ||
| 81 | #######################  | 
            ||
| 82 | |||
| 83 | private static $field_labels = [  | 
            ||
| 84 | 'StyledImages' => 'Images to be included'  | 
            ||
| 85 | ];  | 
            ||
| 86 | |||
| 87 | private static $field_labels_right = [  | 
            ||
| 88 | 'StyledImages' => 'Select as many as you like and sort them in the right order'  | 
            ||
| 89 | ];  | 
            ||
| 90 | |||
| 91 | private static $summary_fields = [  | 
            ||
| 92 | 'Title' => 'Name',  | 
            ||
| 93 | 'StyledImages.Count' => 'Number of Images'  | 
            ||
| 94 | ];  | 
            ||
| 95 | |||
| 96 | |||
| 97 | #######################  | 
            ||
| 98 | ### Casting Section  | 
            ||
| 99 | #######################  | 
            ||
| 100 | |||
| 101 | |||
| 102 | #######################  | 
            ||
| 103 | ### can Section  | 
            ||
| 104 | #######################  | 
            ||
| 105 | |||
| 106 | |||
| 107 | |||
| 108 | #######################  | 
            ||
| 109 | ### write Section  | 
            ||
| 110 | #######################  | 
            ||
| 111 | |||
| 112 | |||
| 113 | |||
| 114 | |||
| 115 | View Code Duplication | public function validate()  | 
            |
| 160 | |||
| 161 | public function onBeforeWrite()  | 
            ||
| 166 | |||
| 167 | public function onAfterWrite()  | 
            ||
| 191 | |||
| 192 | public function requireDefaultRecords()  | 
            ||
| 197 | |||
| 198 | |||
| 199 | #######################  | 
            ||
| 200 | ### Import / Export Section  | 
            ||
| 201 | #######################  | 
            ||
| 202 | |||
| 203 | public function getExportFields()  | 
            ||
| 208 | |||
| 209 | |||
| 210 | |||
| 211 | #######################  | 
            ||
| 212 | ### CMS Edit Section  | 
            ||
| 213 | #######################  | 
            ||
| 214 | |||
| 215 | |||
| 216 | public function CMSEditLink()  | 
            ||
| 222 | |||
| 223 | public function CMSAddLink()  | 
            ||
| 229 | |||
| 230 | |||
| 231 | public function getCMSFields()  | 
            ||
| 281 | |||
| 282 | /**  | 
            ||
| 283 | * @return DataList  | 
            ||
| 284 | */  | 
            ||
| 285 | public function RawImages()  | 
            ||
| 298 | |||
| 299 | /**  | 
            ||
| 300 | * force the list to use a certain folder ...  | 
            ||
| 301 | * @param string $folderName  | 
            ||
| 302 | * @return ImagesWithStyleSelection  | 
            ||
| 303 | */  | 
            ||
| 304 | public function createFolder($folderName)  | 
            ||
| 312 | }  | 
            ||
| 313 | 
You can fix this by adding a namespace to your class:
When choosing a vendor namespace, try to pick something that is not too generic to avoid conflicts with other libraries.