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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| 3 | class ApprovalsDispatcher extends Dispatcher { | 
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| 4 | |||
| 5 | const ACTION_APPROVALS = 'approvals';  | 
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| 6 | |||
| 7 | /**  | 
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| 8 | * @var array  | 
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| 9 | */  | 
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| 10 | public static $allowed_actions = [  | 
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| 11 | 'approvers',  | 
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| 12 | 'approve',  | 
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| 13 | 'reject'  | 
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| 14 | ];  | 
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| 15 | |||
| 16 | /**  | 
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| 17 | * @var \DNProject  | 
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| 18 | */  | 
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| 19 | protected $project = null;  | 
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| 20 | |||
| 21 | /**  | 
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| 22 | * @var \DNEnvironment  | 
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| 23 | */  | 
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| 24 | protected $environment = null;  | 
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| 25 | |||
| 26 | /**  | 
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| 27 | * @var array  | 
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| 28 | */  | 
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| 29 | private static $action_types = [  | 
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| 30 | self::ACTION_APPROVALS  | 
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| 31 | ];  | 
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| 32 | |||
| 33 | 	public function init() { | 
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| 41 | |||
| 42 | /**  | 
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| 43 | * @param \SS_HTTPRequest $request  | 
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| 44 | * @return \SS_HTTPResponse  | 
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| 45 | */  | 
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| 46 | 	public function approvers(SS_HTTPRequest $request) { | 
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| 63 | |||
| 64 | /**  | 
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| 65 | * @param \SS_HTTPRequest $request  | 
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| 66 | * @return \SS_HTTPResponse  | 
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| 67 | */  | 
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| 68 | 	public function submit(SS_HTTPRequest $request) { | 
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| 75 | |||
| 76 | /**  | 
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| 77 | * @param \SS_HTTPRequest $request  | 
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| 78 | * @return \SS_HTTPResponse  | 
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| 79 | */  | 
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| 80 | View Code Duplication | 	public function approve(SS_HTTPRequest $request) { | 
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| 108 | |||
| 109 | /**  | 
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| 110 | * @param \SS_HTTPRequest $request  | 
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| 111 | * @return \SS_HTTPResponse  | 
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| 112 | */  | 
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| 113 | View Code Duplication | 	public function reject(SS_HTTPRequest $request) { | 
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| 143 | |||
| 144 | /**  | 
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| 145 | * Check if a DNDeployment exists and do permission checks on it. If there is something wrong it will return  | 
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| 146 | * an APIResponse with the error, otherwise null.  | 
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| 147 | *  | 
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| 148 | * @param \DNDeployment $deployment  | 
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| 149 | *  | 
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| 150 | * @return null|SS_HTTPResponse  | 
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| 151 | */  | 
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| 152 | View Code Duplication | 	protected function validateDeployment(\DNDeployment $deployment) { | 
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| 161 | |||
| 162 | 	protected function canApprove(Member $member = null) { | 
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| 184 | |||
| 185 | /**  | 
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| 186 | * @param string $name  | 
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| 187 | *  | 
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| 188 | * @return array  | 
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| 189 | */  | 
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| 190 | 	public function getModel($name = '') { | 
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| 193 | |||
| 194 | /**  | 
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| 195 | * @param string $action  | 
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| 196 | * @return string  | 
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| 197 | */  | 
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| 198 | 	public function Link($action = '') { | 
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| 201 | |||
| 202 | }  | 
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| 203 | 
This check marks property names that have not been written in camelCase.
In camelCase names are written without any punctuation, the start of each new word being marked by a capital letter. Thus the name database connection string becomes
databaseConnectionString.