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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| 7 | class LDAPMemberExtension extends DataExtension  | 
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| 8 | { | 
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| 9 | /**  | 
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| 10 | * @var array  | 
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| 11 | */  | 
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| 12 | private static $db = array(  | 
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| 13 | // Unique user identifier, same field is used by SAMLMemberExtension  | 
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| 14 | 'GUID' => 'Varchar(50)',  | 
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| 15 | 'Username' => 'Varchar(64)',  | 
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| 16 | 'IsImportedFromLDAP' => 'Boolean',  | 
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| 17 | 'IsExpired' => 'Boolean',  | 
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| 18 | 'LastSynced' => 'SS_Datetime',  | 
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| 19 | );  | 
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| 20 | |||
| 21 | /**  | 
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| 22 |      * These fields are used by {@link LDAPMemberSync} to map specific AD attributes | 
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| 23 |      * to {@link Member} fields. | 
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| 24 | *  | 
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| 25 | * @var array  | 
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| 26 | * @config  | 
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| 27 | */  | 
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| 28 | private static $ldap_field_mappings = array(  | 
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| 29 | 'givenname' => 'FirstName',  | 
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| 30 | 'samaccountname' => 'Username',  | 
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| 31 | 'sn' => 'Surname',  | 
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| 32 | 'mail' => 'Email',  | 
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| 33 | );  | 
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| 34 | |||
| 35 | /**  | 
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| 36 | * The location (relative to /assets) where to save thumbnailphoto data.  | 
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| 37 | *  | 
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| 38 | * @var string  | 
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| 39 | * @config  | 
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| 40 | */  | 
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| 41 | private static $ldap_thumbnail_path = 'Uploads';  | 
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| 42 | |||
| 43 | /**  | 
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| 44 | * When enabled, LDAP managed Member records (IsImportedFromLDAP flag)  | 
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| 45 | * have their data written back to LDAP on write.  | 
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| 46 | *  | 
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| 47 | * This requires setting write permissions on the user configured in the LDAP  | 
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| 48 | * credentials, which is why this is disabled by default.  | 
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| 49 | *  | 
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| 50 | * @var bool  | 
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| 51 | * @config  | 
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| 52 | */  | 
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| 53 | private static $update_ldap_from_local = false;  | 
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| 54 | |||
| 55 | /**  | 
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| 56 | * If enabled, Member records with a Username field have the user created in LDAP  | 
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| 57 | * on write.  | 
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| 58 | *  | 
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| 59 | * This requires setting write permissions on the user configured in the LDAP  | 
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| 60 | * credentials, which is why this is disabled by default.  | 
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| 61 | *  | 
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| 62 | * Note that some constants must be configured in your environment file:  | 
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| 63 | * LDAP_NEW_USERS_DN - where to place users in the directory. e.g. "OU=Users,DC=mydomain,DC=com"  | 
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| 64 | *  | 
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| 65 | * @var bool  | 
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| 66 | * @config  | 
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| 67 | */  | 
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| 68 | private static $create_users_in_ldap = false;  | 
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| 69 | |||
| 70 | /**  | 
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| 71 | * If enabled, deleting Member records mapped to LDAP deletes the LDAP user.  | 
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| 72 | *  | 
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| 73 | * This requires setting write permissions on the user configured in the LDAP  | 
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| 74 | * credentials, which is why this is disabled by default.  | 
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| 75 | *  | 
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| 76 | * @var bool  | 
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| 77 | * @config  | 
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| 78 | */  | 
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| 79 | private static $delete_users_in_ldap = false;  | 
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| 80 | |||
| 81 | /**  | 
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| 82 | * @param FieldList $fields  | 
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| 83 | */  | 
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| 84 | public function updateCMSFields(FieldList $fields)  | 
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| 138 | |||
| 139 | public function validate(ValidationResult $validationResult)  | 
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| 160 | |||
| 161 | /**  | 
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| 162 | * Create the user in LDAP, provided this configuration is enabled  | 
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| 163 | * and a username was passed to a new Member record.  | 
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| 164 | */  | 
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| 165 | View Code Duplication | public function onBeforeWrite()  | 
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| 178 | |||
| 179 | /**  | 
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| 180 | * Update the local data with LDAP, and ensure local membership is also set in  | 
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| 181 | * LDAP too. This writes into LDAP, provided that feature is enabled.  | 
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| 182 | */  | 
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| 183 | View Code Duplication | public function onAfterWrite()  | 
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| 197 | |||
| 198 | View Code Duplication |     public function onAfterDelete() { | 
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| 210 | |||
| 211 | /**  | 
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| 212 |      * Triggered by {@link Member::logIn()} when successfully logged in, | 
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| 213 | * this will update the Member record from AD data.  | 
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| 214 | */  | 
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| 215 | public function memberLoggedIn()  | 
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| 221 | }  | 
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| 222 | 
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.