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 AbstractHandler 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 AbstractHandler, and based on these observations, apply Extract Interface, too.
1 | <?php |
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24 | abstract class AbstractHandler |
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25 | { |
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26 | /** |
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27 | * Behaviours. |
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28 | */ |
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29 | const DROP_FOREIGNS = 0b000000001; |
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30 | const CREATE_FOREIGNS = 0b000000010; |
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31 | const ALTER_FOREIGNS = 0b000000100; |
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32 | |||
33 | //All foreign keys related operations |
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34 | const DO_FOREIGNS = self::DROP_FOREIGNS | self::ALTER_FOREIGNS | self::CREATE_FOREIGNS; |
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35 | |||
36 | const DROP_COLUMNS = 0b000001000; |
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37 | const CREATE_COLUMNS = 0b000010000; |
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38 | const ALTER_COLUMNS = 0b000100000; |
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39 | |||
40 | //All columns related operations |
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41 | const DO_COLUMNS = self::DROP_COLUMNS | self::ALTER_COLUMNS | self::CREATE_COLUMNS; |
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42 | |||
43 | const DROP_INDEXES = 0b001000000; |
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44 | const CREATE_INDEXES = 0b010000000; |
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45 | const ALTER_INDEXES = 0b100000000; |
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46 | |||
47 | //All index related operations |
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48 | const DO_INDEXES = self::DROP_INDEXES | self::ALTER_INDEXES | self::CREATE_INDEXES; |
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49 | |||
50 | //All operations |
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51 | const DO_ALL = self::DO_FOREIGNS | self::DO_INDEXES | self::DO_COLUMNS; |
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52 | |||
53 | /** |
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54 | * @var LoggerInterface|null |
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55 | */ |
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56 | private $logger = null; |
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57 | |||
58 | /** |
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59 | * @var Driver |
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60 | */ |
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61 | protected $driver; |
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62 | |||
63 | /** |
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64 | * @param Driver $driver |
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65 | * @param LoggerInterface|null $logger |
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66 | */ |
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67 | public function __construct(Driver $driver, LoggerInterface $logger = null) |
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72 | |||
73 | /** |
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74 | * Associated driver. |
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75 | * |
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76 | * @return Driver |
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77 | */ |
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78 | public function getDriver(): Driver |
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82 | |||
83 | /** |
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84 | * Create table based on a given schema. |
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85 | * |
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86 | * @param AbstractTable $table |
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87 | * |
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88 | * @throws HandlerException |
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89 | */ |
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90 | public function createTable(AbstractTable $table) |
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102 | |||
103 | /** |
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104 | * Drop table from database. |
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105 | * |
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106 | * @param AbstractTable $table |
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107 | * |
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108 | * @throws HandlerException |
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109 | */ |
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110 | public function dropTable(AbstractTable $table) |
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116 | |||
117 | /** |
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118 | * Sync given table schema. |
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119 | * |
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120 | * @param AbstractTable $table |
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121 | * @param int $behaviour See behaviour constants. |
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122 | */ |
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123 | public function syncTable(AbstractTable $table, int $behaviour = self::DO_ALL) |
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177 | |||
178 | /** |
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179 | * Rename table from one name to another. |
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180 | * |
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181 | * @param string $table |
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182 | * @param string $name |
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183 | * |
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184 | * @throws HandlerException |
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185 | */ |
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186 | public function renameTable(string $table, string $name) |
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190 | |||
191 | /** |
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192 | * Driver specific column add command. |
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193 | * |
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194 | * @param AbstractTable $table |
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195 | * @param AbstractColumn $column |
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196 | * |
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197 | * @throws HandlerException |
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198 | */ |
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199 | public function createColumn(AbstractTable $table, AbstractColumn $column) |
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203 | |||
204 | /** |
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205 | * Driver specific column remove (drop) command. |
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206 | * |
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207 | * @param AbstractTable $table |
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208 | * @param AbstractColumn $column |
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209 | * |
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210 | * @return self |
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211 | */ |
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212 | public function dropColumn(AbstractTable $table, AbstractColumn $column) |
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221 | |||
222 | /** |
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223 | * Driver specific column alter command. |
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224 | * |
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225 | * @param AbstractTable $table |
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226 | * @param AbstractColumn $initial |
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227 | * @param AbstractColumn $column |
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228 | * |
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229 | * @throws HandlerException |
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230 | */ |
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231 | abstract public function alterColumn( |
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236 | |||
237 | /** |
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238 | * Driver specific index adding command. |
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239 | * |
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240 | * @param AbstractTable $table |
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241 | * @param AbstractIndex $index |
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242 | * |
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243 | * @throws HandlerException |
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244 | */ |
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245 | public function createIndex(AbstractTable $table, AbstractIndex $index) |
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249 | |||
250 | /** |
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251 | * Driver specific index remove (drop) command. |
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252 | * |
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253 | * @param AbstractTable $table |
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254 | * @param AbstractIndex $index |
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255 | * |
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256 | * @throws HandlerException |
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257 | */ |
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258 | public function dropIndex(AbstractTable $table, AbstractIndex $index) |
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262 | |||
263 | /** |
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264 | * Driver specific index alter command, by default it will remove and add index. |
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265 | * |
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266 | * @param AbstractTable $table |
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267 | * @param AbstractIndex $initial |
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268 | * @param AbstractIndex $index |
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269 | * |
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270 | * @throws HandlerException |
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271 | */ |
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272 | public function alterIndex(AbstractTable $table, AbstractIndex $initial, AbstractIndex $index) |
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277 | |||
278 | /** |
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279 | * Driver specific foreign key adding command. |
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280 | * |
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281 | * @param AbstractTable $table |
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282 | * @param AbstractReference $foreign |
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283 | * |
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284 | * @throws HandlerException |
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285 | */ |
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286 | public function createForeign(AbstractTable $table, AbstractReference $foreign) |
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290 | |||
291 | /** |
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292 | * Driver specific foreign key remove (drop) command. |
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293 | * |
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294 | * @param AbstractTable $table |
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295 | * @param AbstractReference $foreign |
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296 | * |
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297 | * @throws HandlerException |
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298 | */ |
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299 | public function dropForeign(AbstractTable $table, AbstractReference $foreign) |
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303 | |||
304 | /** |
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305 | * Driver specific foreign key alter command, by default it will remove and add foreign key. |
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306 | * |
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307 | * @param AbstractTable $table |
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308 | * @param AbstractReference $initial |
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309 | * @param AbstractReference $foreign |
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310 | * |
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311 | * @throws HandlerException |
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312 | */ |
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313 | public function alterForeign( |
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321 | |||
322 | /** |
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323 | * Drop column constraint using it's name. |
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324 | * |
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325 | * @param AbstractTable $table |
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326 | * @param string $constraint |
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327 | * |
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328 | * @throws HandlerException |
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329 | */ |
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330 | public function dropConstrain(AbstractTable $table, $constraint) |
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334 | |||
335 | /** |
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336 | * Get statement needed to create table. Indexes will be created separately. |
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337 | * |
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338 | * @param AbstractTable $table |
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339 | * |
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340 | * @return string |
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341 | */ |
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342 | protected function createStatement(AbstractTable $table) |
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369 | |||
370 | /** |
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371 | * Execute statement. |
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372 | * |
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373 | * @param string $statement |
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374 | * @param array $parameters |
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375 | * |
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376 | * @return \PDOStatement |
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377 | * |
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378 | * @throws HandlerException |
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379 | */ |
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380 | protected function run(string $statement, array $parameters = []): \PDOStatement |
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388 | |||
389 | /** |
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390 | * Helper function, saves log message into logger if any attached. |
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391 | * |
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392 | * @param string $message |
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393 | * @param array $context |
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394 | */ |
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395 | protected function log(string $message, array $context = []) |
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401 | |||
402 | /** |
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403 | * Create element identifier. |
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404 | * |
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405 | * @param AbstractElement|AbstractTable|string $element |
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406 | * |
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407 | * @return string |
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408 | */ |
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409 | protected function identify($element) |
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421 | |||
422 | /** |
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423 | * @param AbstractTable $table |
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424 | * @param StateComparator $comparator |
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425 | */ |
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426 | View Code Duplication | protected function alterForeigns(AbstractTable $table, StateComparator $comparator) |
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443 | |||
444 | /** |
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445 | * @param AbstractTable $table |
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446 | * @param StateComparator $comparator |
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447 | */ |
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448 | View Code Duplication | protected function createForeigns(AbstractTable $table, StateComparator $comparator) |
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459 | |||
460 | /** |
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461 | * @param AbstractTable $table |
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462 | * @param StateComparator $comparator |
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463 | */ |
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464 | View Code Duplication | protected function alterIndexes(AbstractTable $table, StateComparator $comparator) |
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482 | |||
483 | /** |
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484 | * @param AbstractTable $table |
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485 | * @param StateComparator $comparator |
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486 | */ |
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487 | View Code Duplication | protected function createIndexes(AbstractTable $table, StateComparator $comparator) |
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498 | |||
499 | /** |
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500 | * @param AbstractTable $table |
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501 | * @param StateComparator $comparator |
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502 | */ |
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503 | View Code Duplication | protected function alterColumns(AbstractTable $table, StateComparator $comparator) |
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521 | |||
522 | /** |
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523 | * @param AbstractTable $table |
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524 | * @param StateComparator $comparator |
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525 | */ |
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526 | View Code Duplication | protected function createColumns(AbstractTable $table, StateComparator $comparator) |
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537 | |||
538 | /** |
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539 | * @param AbstractTable $table |
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540 | * @param StateComparator $comparator |
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541 | */ |
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542 | View Code Duplication | protected function dropColumns(AbstractTable $table, StateComparator $comparator) |
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553 | |||
554 | /** |
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555 | * @param AbstractTable $table |
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556 | * @param StateComparator $comparator |
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557 | */ |
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558 | View Code Duplication | protected function dropIndexes(AbstractTable $table, StateComparator $comparator) |
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569 | |||
570 | /** |
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571 | * @param AbstractTable $table |
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572 | * @param StateComparator $comparator |
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573 | */ |
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574 | View Code Duplication | protected function dropForeigns(AbstractTable $table, $comparator) |
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585 | } |
This check looks for parameters that are defined as one type in their type hint or doc comment but seem to be used as a narrower type, i.e an implementation of an interface or a subclass.
Consider changing the type of the parameter or doing an instanceof check before assuming your parameter is of the expected type.