Complex classes like Filterer 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 Filterer, and based on these observations, apply Extract Interface, too.
| 1 | <?php | ||
| 13 | class Filterer | ||
| 14 | { | ||
| 15 | /** | ||
| 16 | * @var array | ||
| 17 | */ | ||
| 18 | private $uniqueNameToQueryFieldMap; | ||
| 19 | |||
| 20 | /** | ||
| 21 | * Apply the filters to the query builders | ||
| 22 | * | ||
| 23 | * @param QueryBuilder $queryBuilder | ||
| 24 | * @param Filter $filterDefinition | ||
| 25 | * @param array $uniqueNameToQueryFieldMap | ||
| 26 | * | ||
| 27 | * @return QueryBuilder | ||
| 28 | * @throws \Exception | ||
| 29 | */ | ||
| 30 | public function filter(QueryBuilder $queryBuilder, Filter $filterDefinition, $uniqueNameToQueryFieldMap) | ||
| 40 | |||
| 41 | /** | ||
| 42 | * Builds a filter group and, recursively, constructs a tree of conditions for the filters | ||
| 43 | * | ||
| 44 | * @param QueryBuilder $queryBuilder | ||
| 45 | * @param Filter $filterDefinition | ||
| 46 | * | ||
| 47 | * @throws \Exception | ||
| 48 | * @return Andx|Orx | ||
| 49 | */ | ||
| 50 | private function buildFilterGroup(QueryBuilder $queryBuilder, Filter $filterDefinition) | ||
| 67 | |||
| 68 | /** | ||
| 69 | * @param Composite $expressions | ||
| 70 | * @param Filter $filterDefinition | ||
| 71 | * @param QueryBuilder $queryBuilder | ||
| 72 | * | ||
| 73 | * @throws \Exception | ||
| 74 | */ | ||
| 75 | private function addExpressionsForFilter(Composite $expressions, Filter $filterDefinition, QueryBuilder $queryBuilder) | ||
| 86 | |||
| 87 | /** | ||
| 88 | * @param Composite $expressions | ||
| 89 | * @param FilterCondition $filterCondition | ||
| 90 | * @param QueryBuilder $queryBuilder | ||
| 91 | * | ||
| 92 | * @throws \Exception | ||
| 93 | */ | ||
| 94 | private function addExpressionsForFilterCondition(Composite $expressions, FilterCondition $filterCondition, QueryBuilder $queryBuilder) | ||
| 103 | |||
| 104 | /** | ||
| 105 | * @param FilterCondition $filterCondition | ||
| 106 | * @param QueryBuilder $queryBuilder | ||
| 107 | * | ||
| 108 | * @return string | ||
| 109 | */ | ||
| 110 | private function buildUniqueToken(FilterCondition $filterCondition, QueryBuilder $queryBuilder) | ||
| 116 | |||
| 117 | /** | ||
| 118 | * @param FilterCondition $filterCondition | ||
| 119 | * @param string $token | ||
| 120 | * @param QueryBuilder $queryBuilder | ||
| 121 | * | ||
| 122 | * @throws \Exception | ||
| 123 | * | ||
| 124 | * @return Expr|string | ||
| 125 | */ | ||
| 126 | private function buildExpression(FilterCondition $filterCondition, $token, QueryBuilder $queryBuilder) | ||
| 166 | |||
| 167 | /** | ||
| 168 | * @param FilterCondition $filterCondition | ||
| 169 | * @param string $identifier | ||
| 170 | * @param QueryBuilder $queryBuilder | ||
| 171 | * | ||
| 172 | * @return Andx|Orx | ||
| 173 | * | ||
| 174 | * @throws \Exception | ||
| 175 | */ | ||
| 176 | private function buildExpressionForNullValue(FilterCondition $filterCondition, $identifier, QueryBuilder $queryBuilder) | ||
| 206 | |||
| 207 | /** | ||
| 208 | * @param FilterCondition $filterCondition | ||
| 209 | * @param string $identifier | ||
| 210 | * @param string $token | ||
| 211 | * @param QueryBuilder $queryBuilder | ||
| 212 | * | ||
| 213 | * @return Andx|Orx|string | ||
| 214 | * | ||
| 215 | * @throws \Exception | ||
| 216 | */ | ||
| 217 | private function buildExpressionForCollection(FilterCondition $filterCondition, $identifier, $token, QueryBuilder $queryBuilder) | ||
| 240 | |||
| 241 | /** | ||
| 242 | * @param FilterCondition $filterCondition | ||
| 243 | * @param string $token | ||
| 244 | * @param QueryBuilder $queryBuilder | ||
| 245 | */ | ||
| 246 | private function setExpressionParameters(FilterCondition $filterCondition, $token, QueryBuilder $queryBuilder) | ||
| 267 | } | ||
| 268 |