Complex classes like QueryHelper 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 QueryHelper, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 19 | */ |
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| 20 | class QueryHelper |
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| 21 | { |
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| 22 | /** |
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| 23 | * @var array |
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| 24 | */ |
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| 25 | protected static $operators = ['not ', '!=', '<=', '>=', '<', '>', '=']; |
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| 26 | |||
| 27 | /** |
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| 28 | * @param $condition |
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| 29 | * @return array |
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| 30 | */ |
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| 31 | public static function conditionToCriteria($condition) |
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| 46 | |||
| 47 | /** |
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| 48 | * @param QueryInterface|Query $query |
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| 49 | * @param array $config |
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| 50 | * @return QueryInterface |
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| 51 | */ |
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| 52 | public static function configure(QueryInterface $query, $config = []): QueryInterface |
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| 73 | |||
| 74 | /** |
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| 75 | * Standard param parsing. |
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| 76 | * |
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| 77 | * @param $value |
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| 78 | * @param $join |
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| 79 | * @return bool |
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| 80 | */ |
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| 81 | public static function parseBaseParam(&$value, &$join): bool |
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| 99 | |||
| 100 | /** |
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| 101 | * Attempt to resolve a param value by the value. |
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| 102 | * Return false if a 'handle' or other string identifier is detected. |
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| 103 | * |
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| 104 | * @param $value |
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| 105 | * @param $operator |
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| 106 | * @return bool |
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| 107 | */ |
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| 108 | public static function findParamValue(&$value, &$operator): bool |
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| 133 | |||
| 134 | /** |
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| 135 | * Format the param value so that we return a string w/ a prepended operator. |
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| 136 | * |
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| 137 | * @param $value |
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| 138 | * @param $operator |
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| 139 | * @param string|int|mixed $defaultValue |
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| 140 | * @return array|string |
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| 141 | */ |
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| 142 | public static function assembleParamValue($value, $operator, $defaultValue = ':default:') |
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| 158 | |||
| 159 | /** |
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| 160 | * Attempt to resolve a param value by the value. |
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| 161 | * Return false if a 'handle' or other string identifier is detected. |
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| 162 | * |
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| 163 | * @param $value |
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| 164 | * @param $operator |
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| 165 | * @return bool |
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| 166 | */ |
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| 167 | public static function prepParamValue(&$value, &$operator): bool |
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| 192 | |||
| 193 | /** |
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| 194 | * @param $value |
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| 195 | * @param string $default |
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| 196 | * @return mixed|string |
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| 197 | */ |
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| 198 | private static function getJoinType(&$value, $default = 'or') |
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| 215 | |||
| 216 | /** |
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| 217 | * Attempt to get a numeric value from an object array. |
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| 218 | * @param $value |
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| 219 | * @param null $operator |
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| 220 | * @return mixed|string |
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| 221 | */ |
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| 222 | private static function findIdFromObjectArray($value, $operator = null) |
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| 230 | |||
| 231 | /** |
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| 232 | * Prepend the operator to a value |
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| 233 | * |
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| 234 | * @param $value |
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| 235 | * @param null $operator |
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| 236 | * @return string|array |
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| 237 | */ |
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| 238 | private static function prependOperator($value, $operator = null) |
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| 261 | |||
| 262 | /** |
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| 263 | * Normalizes “empty” values. |
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| 264 | * |
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| 265 | * @param string &$value The param value. |
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| 266 | */ |
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| 267 | private static function normalizeEmptyValue(&$value) |
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| 277 | |||
| 278 | /** |
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| 279 | * Extracts the operator from a DB param and returns it. |
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| 280 | * |
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| 281 | * @param string &$value Te param value. |
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| 282 | * |
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| 283 | * @return string The operator. |
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| 284 | */ |
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| 285 | private static function parseParamOperator(&$value) |
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| 286 | { |
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| 287 | foreach (static::$operators as $testOperator) { |
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| 288 | // Does the value start with this operator? |
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| 289 | $operatorLength = strlen($testOperator); |
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| 310 |
Let’s assume that you have a directory layout like this:
. |-- OtherDir | |-- Bar.php | `-- Foo.php `-- SomeDir `-- Foo.phpand let’s assume the following content of
Bar.php:If both files
OtherDir/Foo.phpandSomeDir/Foo.phpare loaded in the same runtime, you will see a PHP error such as the following:PHP Fatal error: Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.phpHowever, as
OtherDir/Foo.phpdoes not necessarily have to be loaded and the error is only triggered if it is loaded beforeOtherDir/Bar.php, this problem might go unnoticed for a while. In order to prevent this error from surfacing, you must import the namespace with a different alias: