Complex classes like StatementList 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 StatementList, and based on these observations, apply Extract Interface, too.
| 1 | <?php | ||
| 31 | class StatementList implements IteratorAggregate, Comparable, Countable { | ||
| 32 | |||
| 33 | /** | ||
| 34 | * @var Statement[] | ||
| 35 | */ | ||
| 36 | private $statements = []; | ||
| 37 | |||
| 38 | /** | ||
| 39 | * @param Statement[]|Traversable|Statement $statements | ||
| 40 | * @param Statement [$statement2,...] | ||
| 41 | * | ||
| 42 | * @throws InvalidArgumentException | ||
| 43 | */ | ||
| 44 | 	public function __construct( $statements = [] /*...*/ ) { | ||
| 61 | |||
| 62 | /** | ||
| 63 | * Returns the property ids used by the statements. | ||
| 64 | * The keys of the returned array hold the serializations of the property ids. | ||
| 65 | * | ||
| 66 | * @return PropertyId[] Array indexed by property id serialization. | ||
| 67 | */ | ||
| 68 | 	public function getPropertyIds() { | ||
| 77 | |||
| 78 | /** | ||
| 79 | * @since 1.0, setting an index is supported since 6.1 | ||
| 80 | * @see ReferenceList::addReference | ||
| 81 | * | ||
| 82 | * @param Statement $statement | ||
| 83 | * @param int|null $index New position of the added statement, or null to append. | ||
| 84 | * | ||
| 85 | * @throws InvalidArgumentException | ||
| 86 | */ | ||
| 87 | 	public function addStatement( Statement $statement, $index = null ) { | ||
| 88 | 		if ( $index === null ) { | ||
| 89 | $this->statements[] = $statement; | ||
| 90 | 		} elseif ( is_int( $index ) && $index >= 0 ) { | ||
| 91 | array_splice( $this->statements, $index, 0, [ $statement ] ); | ||
| 92 | 		} else { | ||
| 93 | throw new InvalidArgumentException( '$index must be a non-negative integer or null' ); | ||
| 94 | } | ||
| 95 | } | ||
| 96 | |||
| 97 | /** | ||
| 98 | * @param Snak $mainSnak | ||
| 99 | * @param Snak[]|SnakList|null $qualifiers | ||
| 100 | * @param Reference[]|ReferenceList|null $references | ||
| 101 | * @param string|null $guid | ||
| 102 | */ | ||
| 103 | 	public function addNewStatement( Snak $mainSnak, $qualifiers = null, $references = null, $guid = null ) { | ||
| 104 | $qualifiers = is_array( $qualifiers ) ? new SnakList( $qualifiers ) : $qualifiers; | ||
| 105 | $references = is_array( $references ) ? new ReferenceList( $references ) : $references; | ||
| 106 | |||
| 107 | $statement = new Statement( $mainSnak, $qualifiers, $references ); | ||
| 108 | $statement->setGuid( $guid ); | ||
| 109 | |||
| 110 | $this->statements[] = $statement; | ||
| 111 | } | ||
| 112 | |||
| 113 | /** | ||
| 114 | * @since 3.0 | ||
| 115 | * | ||
| 116 | * @param string|null $guid | ||
| 117 | */ | ||
| 118 | 	public function removeStatementsWithGuid( $guid ) { | ||
| 127 | |||
| 128 | /** | ||
| 129 | * Statements that have a main snak already in the list are filtered out. | ||
| 130 | * The last occurrences are retained. | ||
| 131 | * | ||
| 132 | * @since 1.0 | ||
| 133 | * | ||
| 134 | * @return self | ||
| 135 | */ | ||
| 136 | 	public function getWithUniqueMainSnaks() { | ||
| 137 | $statements = []; | ||
| 138 | |||
| 139 | 		foreach ( $this->statements as $statement ) { | ||
| 140 | $statements[$statement->getMainSnak()->getHash()] = $statement; | ||
| 141 | } | ||
| 142 | |||
| 143 | return new self( $statements ); | ||
| 144 | } | ||
| 145 | |||
| 146 | /** | ||
| 147 | * @since 3.0 | ||
| 148 | * | ||
| 149 | * @param PropertyId $id | ||
| 150 | * | ||
| 151 | * @return self | ||
| 152 | */ | ||
| 153 | 	public function getByPropertyId( PropertyId $id ) { | ||
| 164 | |||
| 165 | /** | ||
| 166 | * @since 3.0 | ||
| 167 | * | ||
| 168 | * @param int|int[] $acceptableRanks | ||
| 169 | * | ||
| 170 | * @return self | ||
| 171 | */ | ||
| 172 | 	public function getByRank( $acceptableRanks ) { | ||
| 173 | $acceptableRanks = array_flip( (array)$acceptableRanks ); | ||
| 174 | $statementList = new self(); | ||
| 175 | |||
| 176 | 		foreach ( $this->statements as $statement ) { | ||
| 177 | 			if ( array_key_exists( $statement->getRank(), $acceptableRanks ) ) { | ||
| 178 | $statementList->statements[] = $statement; | ||
| 179 | } | ||
| 180 | } | ||
| 181 | |||
| 182 | return $statementList; | ||
| 183 | } | ||
| 184 | |||
| 185 | /** | ||
| 186 | * Returns the so called "best statements". | ||
| 187 | * If there are preferred statements, then this is all the preferred statements. | ||
| 188 | * If there are no preferred statements, then this is all normal statements. | ||
| 189 | * | ||
| 190 | * @since 2.4 | ||
| 191 | * | ||
| 192 | * @return self | ||
| 193 | */ | ||
| 194 | 	public function getBestStatements() { | ||
| 203 | |||
| 204 | /** | ||
| 205 | * Returns a list of all Snaks on this StatementList. This includes at least the main snaks of | ||
| 206 | * all statements, the snaks from qualifiers, and the snaks from references. | ||
| 207 | * | ||
| 208 | * This is a convenience method for use in code that needs to operate on all snaks, e.g. | ||
| 209 | * to find all referenced Entities. | ||
| 210 | * | ||
| 211 | * @since 1.1 | ||
| 212 | * | ||
| 213 | * @return Snak[] Numerically indexed (non-sparse) array. | ||
| 214 | */ | ||
| 215 | 	public function getAllSnaks() { | ||
| 226 | |||
| 227 | /** | ||
| 228 | * @since 2.3 | ||
| 229 | * | ||
| 230 | * @return Snak[] Numerically indexed (non-sparse) array. | ||
| 231 | */ | ||
| 232 | 	public function getMainSnaks() { | ||
| 241 | |||
| 242 | /** | ||
| 243 | * @return Traversable|Statement[] | ||
| 244 | */ | ||
| 245 | 	public function getIterator() { | ||
| 248 | |||
| 249 | /** | ||
| 250 | * @return Statement[] Numerically indexed (non-sparse) array. | ||
| 251 | */ | ||
| 252 | 	public function toArray() { | ||
| 255 | |||
| 256 | /** | ||
| 257 | * @see Countable::count | ||
| 258 | * | ||
| 259 | * @return int | ||
| 260 | */ | ||
| 261 | 	public function count() { | ||
| 264 | |||
| 265 | /** | ||
| 266 | * @see Comparable::equals | ||
| 267 | * | ||
| 268 | * @param mixed $target | ||
| 269 | * | ||
| 270 | * @return bool | ||
| 271 | */ | ||
| 272 | 	public function equals( $target ) { | ||
| 285 | |||
| 286 | 	private function statementsEqual( array $statements ) { | ||
| 299 | |||
| 300 | /** | ||
| 301 | * @return bool | ||
| 302 | */ | ||
| 303 | 	public function isEmpty() { | ||
| 306 | |||
| 307 | /** | ||
| 308 | * @since 3.0 | ||
| 309 | * @see StatementByGuidMap | ||
| 310 | * | ||
| 311 | * @param string|null $statementGuid | ||
| 312 | * | ||
| 313 | * @return Statement|null The first statement with the given GUID or null if not found. | ||
| 314 | */ | ||
| 315 | 	public function getFirstStatementWithGuid( $statementGuid ) { | ||
| 324 | |||
| 325 | /** | ||
| 326 | * @since 4.1 | ||
| 327 | * | ||
| 328 | * @param StatementFilter $filter | ||
| 329 | * | ||
| 330 | * @return self | ||
| 331 | */ | ||
| 332 | 	public function filter( StatementFilter $filter ) { | ||
| 343 | |||
| 344 | /** | ||
| 345 | * Removes all statements from this list. | ||
| 346 | * | ||
| 347 | * @since 6.0 | ||
| 348 | */ | ||
| 349 | 	public function clear() { | ||
| 352 | |||
| 353 | /** | ||
| 354 | * @see http://php.net/manual/en/language.oop5.cloning.php | ||
| 355 | * | ||
| 356 | * @since 5.1 | ||
| 357 | */ | ||
| 358 | 	public function __clone() { | ||
| 363 | |||
| 364 | } | ||
| 365 |