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 ExperimentMetricResults 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 ExperimentMetricResults, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 15 | class ExperimentMetricResults |
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| 16 | { |
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| 17 | /** |
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| 18 | * The aggregation function for the numerator of the metric. 'unique' measures |
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| 19 | * the number of unique visitors/sessions that include the specified Event. |
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| 20 | * 'count' measures the total number of occurrences of Event for the scope |
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| 21 | * (visitor/session). 'sum' is the sum of the 'field' value. 'exit' measures |
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| 22 | * the ratio of sessions with last activation occurring on the target page to |
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| 23 | * the sessions that activated the target page at least once during the session. |
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| 24 | * 'bounce' measures the ratio of sessions that with first and last activation |
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| 25 | * occurring on the target page to the sessions with first activation on the |
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| 26 | * target page. For both 'exit' and 'bounce', the eventId must be the ID of a Page. |
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| 27 | * |
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| 28 | * @var string |
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| 29 | */ |
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| 30 | private $aggregator; |
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| 31 | |||
| 32 | /** |
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| 33 | * |
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| 34 | * @var string |
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| 35 | */ |
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| 36 | private $eventId; |
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| 37 | |||
| 38 | /** |
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| 39 | * |
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| 40 | * @var string |
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| 41 | */ |
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| 42 | private $eventName; |
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| 43 | |||
| 44 | /** |
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| 45 | * |
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| 46 | * @var type |
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| 47 | */ |
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| 48 | private $field; |
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| 49 | |||
| 50 | /** |
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| 51 | * Conversions indicate the total number of visitors or sessions where the |
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| 52 | * event happened. Impressions indicate the total number of times the event |
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| 53 | * happened (possibly multiple per visitor or session). Revenue indicates |
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| 54 | * the sum of all revenue sent from all events in the Experiment. |
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| 55 | * Can be 'conversions', 'impressions' or 'revenue'. |
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| 56 | * @var string |
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| 57 | */ |
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| 58 | private $measure; |
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| 59 | |||
| 60 | /** |
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| 61 | * |
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| 62 | * @var string |
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| 63 | */ |
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| 64 | private $metricId; |
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| 65 | |||
| 66 | /** |
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| 67 | * |
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| 68 | * @var integer |
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| 69 | */ |
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| 70 | private $priority; |
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| 71 | |||
| 72 | /** |
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| 73 | * Can be 'session', 'visitor' or 'event' |
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| 74 | * @var string |
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| 75 | */ |
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| 76 | private $unit; |
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| 77 | |||
| 78 | /** |
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| 79 | * |
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| 80 | * @var string |
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| 81 | */ |
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| 82 | private $name; |
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| 83 | |||
| 84 | /** |
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| 85 | * A map of results for each variation in the Experiment keyed by variation ID. |
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| 86 | * For Personalization Campaigns, the special variant 'baseline' represents |
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| 87 | * visitors that have been held back from any change in experience for the Experiment |
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| 88 | * |
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| 89 | * @var object[VariantResults] |
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| 90 | */ |
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| 91 | private $results; |
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| 92 | |||
| 93 | /** |
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| 94 | * |
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| 95 | * @var string |
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| 96 | */ |
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| 97 | private $scope; |
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| 98 | |||
| 99 | /** |
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| 100 | * |
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| 101 | * @var type |
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| 102 | */ |
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| 103 | private $winningDirection; |
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| 104 | |||
| 105 | /** |
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| 106 | * Constructor. |
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| 107 | */ |
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| 108 | 3 | public function __construct($options = array()) |
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| 135 | |||
| 136 | /** |
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| 137 | * Returns this object as array. |
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| 138 | */ |
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| 139 | public function toArray() |
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| 156 | |||
| 157 | public function getAggregator() |
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| 161 | |||
| 162 | public function setAggregator($aggregator) |
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| 166 | |||
| 167 | public function getEventId() |
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| 171 | |||
| 172 | public function setEventId($eventId) |
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| 176 | |||
| 177 | public function getEventName() |
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| 181 | |||
| 182 | public function setEventName($eventName) |
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| 186 | |||
| 187 | public function getField() |
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| 191 | |||
| 192 | public function setField($field) |
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| 196 | |||
| 197 | public function getMeasure() |
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| 201 | |||
| 202 | public function setMeasure($measure) |
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| 206 | |||
| 207 | public function getMetricId() |
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| 211 | |||
| 212 | public function setMetricId($metricId) |
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| 216 | |||
| 217 | public function getPriority() |
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| 221 | |||
| 222 | public function setPriority($priority) |
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| 226 | |||
| 227 | public function getUnit() |
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| 231 | |||
| 232 | public function setUnit($unit) |
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| 236 | |||
| 237 | public function getResults() |
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| 241 | |||
| 242 | public function setResults($results) |
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| 246 | |||
| 247 | public function getName() |
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| 251 | |||
| 252 | public function setName($name) |
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| 256 | |||
| 257 | public function getScope() |
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| 261 | |||
| 262 | public function setScope($scope) |
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| 266 | |||
| 267 | public function getWinningDirection() |
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| 271 | |||
| 272 | public function setWinningDirection($winningDirection) |
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| 276 | } |
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| 277 | |||
| 287 |
According to the PSR-2, the body of a case statement must start on the line immediately following the case statement.
}
To learn more about the PSR-2 coding standard, please refer to the PHP-Fig.