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 DeploymentStrategy 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 DeploymentStrategy, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 3 | class DeploymentStrategy extends ViewableData { | 
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| 4 | |||
| 5 | const SUCCESS_CODE = 'success';  | 
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| 6 | |||
| 7 | const WARNING_CODE = 'warning';  | 
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| 8 | |||
| 9 | const ERROR_CODE = 'error';  | 
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| 10 | |||
| 11 | /**  | 
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| 12 | * @var DNEnvironment  | 
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| 13 | */  | 
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| 14 | protected $environment;  | 
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| 15 | |||
| 16 | /**  | 
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| 17 | * @var string  | 
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| 18 | */  | 
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| 19 | protected $actionTitle = 'Deploy';  | 
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| 20 | |||
| 21 | /**  | 
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| 22 | * @var string  | 
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| 23 | */  | 
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| 24 | protected $actionCode = 'default';  | 
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| 25 | |||
| 26 | /**  | 
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| 27 | * @var int  | 
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| 28 | */  | 
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| 29 | protected $estimatedTime = 0;  | 
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| 30 | |||
| 31 | /**  | 
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| 32 | * @var array  | 
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| 33 | */  | 
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| 34 | protected $changes = [];  | 
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| 35 | |||
| 36 | /**  | 
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| 37 | * @var array  | 
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| 38 | */  | 
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| 39 | protected $options;  | 
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| 40 | |||
| 41 | /**  | 
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| 42 | * Validation code  | 
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| 43 | *  | 
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| 44 | * @var string  | 
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| 45 | */  | 
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| 46 | protected $validationCode = DeploymentStrategy::SUCCESS_CODE;  | 
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                         | 
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| 47 | |||
| 48 | /**  | 
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| 49 | * @var array  | 
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| 50 | */  | 
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| 51 | protected $messages = [];  | 
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| 52 | |||
| 53 | |||
| 54 | /**  | 
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| 55 | * @param \DNEnvironment $environment  | 
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| 56 | * @param array $options  | 
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| 57 | */  | 
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| 58 | 	public function __construct(\DNEnvironment $environment, $options = array()) { | 
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| 62 | |||
| 63 | /**  | 
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| 64 | * @param string $title  | 
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| 65 | */  | 
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| 66 | 	public function setActionTitle($title) { | 
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| 69 | |||
| 70 | /**  | 
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| 71 | * @return string  | 
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| 72 | */  | 
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| 73 | 	public function getActionTitle() { | 
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| 76 | |||
| 77 | /**  | 
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| 78 | */  | 
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| 79 | 	public function setActionCode($code) { | 
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| 82 | |||
| 83 | /**  | 
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| 84 | * @return string  | 
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| 85 | */  | 
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| 86 | 	public function getActionCode() { | 
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| 89 | |||
| 90 | /**  | 
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| 91 | * @param int  | 
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| 92 | */  | 
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| 93 | 	public function setEstimatedTime($seconds) { | 
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| 96 | |||
| 97 | /**  | 
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| 98 | * @return int Time in minutes  | 
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| 99 | */  | 
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| 100 | 	public function getEstimatedTime() { | 
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| 103 | |||
| 104 | /**  | 
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| 105 | * @param string $title  | 
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| 106 | * @param string $from  | 
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| 107 | * @param string $to  | 
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| 108 | */  | 
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| 109 | 	public function setChange($title, $from, $to) { | 
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| 121 | |||
| 122 | /**  | 
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| 123 | * @param array $data  | 
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| 124 | */  | 
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| 125 | 	public function setChanges($data) { | 
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| 128 | |||
| 129 | /**  | 
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| 130 | * @param string $title  | 
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| 131 | * @param string $desc  | 
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| 132 | */  | 
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| 133 | 	public function setChangeDescriptionOnly($title, $desc) { | 
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| 138 | |||
| 139 | /**  | 
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| 140 | * Filter the changeset where modification was not required.  | 
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| 141 | *  | 
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| 142 | * @return array  | 
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| 143 | */  | 
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| 144 | 	public function getChangesModificationNeeded() { | 
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| 159 | |||
| 160 | /**  | 
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| 161 | * @return array Associative array of changes, e.g.  | 
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| 162 | * array(  | 
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| 163 | * 'SHA' => array(  | 
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| 164 | * 'from' => 'abc',  | 
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| 165 | * 'to' => 'def'  | 
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| 166 | * )  | 
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| 167 | * )  | 
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| 168 | */  | 
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| 169 | 	public function getChanges() { | 
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| 172 | |||
| 173 | /**  | 
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| 174 | * Returns a change or a given key.  | 
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| 175 | *  | 
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| 176 | * @return ArrayData|null  | 
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| 177 | */  | 
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| 178 | 	public function getChange($key) { | 
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| 185 | |||
| 186 | /**  | 
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| 187 | * @param string $option  | 
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| 188 | * @param string $value  | 
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| 189 | */  | 
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| 190 | 	public function setOption($option, $value) { | 
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| 193 | |||
| 194 | /**  | 
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| 195 | * @param string $option  | 
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| 196 | * @return string|null  | 
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| 197 | */  | 
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| 198 | 	public function getOption($option) { | 
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| 203 | |||
| 204 | /**  | 
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| 205 | * @return string  | 
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| 206 | */  | 
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| 207 | 	public function getOptions() { | 
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| 210 | |||
| 211 | /**  | 
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| 212 | * @param string $code  | 
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| 213 | */  | 
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| 214 | 	public function setValidationCode($code) { | 
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| 217 | |||
| 218 | /**  | 
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| 219 | * @return string  | 
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| 220 | */  | 
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| 221 | 	public function getValidationCode() { | 
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| 224 | |||
| 225 | /**  | 
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| 226 | * @param string $msg  | 
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| 227 | */  | 
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| 228 | 	public function setMessage($msg, $code = self::ERROR_CODE) { | 
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| 244 | |||
| 245 | /**  | 
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| 246 | * @return array  | 
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| 247 | */  | 
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| 248 | 	public function getMessages() { | 
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| 251 | |||
| 252 | /**  | 
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| 253 | * Transform the deployment strategy to an array.  | 
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| 254 | *  | 
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| 255 | * @return array  | 
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| 256 | */  | 
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| 257 | View Code Duplication | 	public function toArray() { | 
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| 274 | |||
| 275 | /**  | 
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| 276 | * @return string  | 
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| 277 | */  | 
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| 278 | 	public function toJSON() { | 
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| 281 | |||
| 282 | /**  | 
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| 283 | * Load from JSON associative array.  | 
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| 284 | * Environment must be set by the callee when creating this object.  | 
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| 285 | *  | 
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| 286 | * @param string $json  | 
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| 287 | */  | 
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| 288 | 	public function fromJSON($json) { | 
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| 292 | |||
| 293 | /**  | 
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| 294 | * Load from array.  | 
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| 295 | * Environment must be set by the callee when creating this object.  | 
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| 296 | *  | 
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| 297 | * @param string $data  | 
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| 298 | */  | 
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| 299 | View Code Duplication | 	public function fromArray($data) { | 
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| 316 | |||
| 317 | /**  | 
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| 318 | * @return DNDeployment  | 
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| 319 | */  | 
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| 320 | 	public function createDeployment() { | 
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| 337 | |||
| 338 | }  | 
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| 339 | |||
| 340 | 
This check looks for accesses to local static members using the fully qualified name instead of
self::.While this is perfectly valid, the fully qualified name of
Certificate::TRIPLEDES_CBCcould just as well be replaced byself::TRIPLEDES_CBC. Referencing local members withself::assured the access will still work when the class is renamed, makes it perfectly clear that the member is in fact local and will usually be shorter.