Complex classes like DbConnection 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 DbConnection, and based on these observations, apply Extract Interface, too.
1 | <?php /** MicroDataBaseConnection */ |
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20 | class DbConnection extends Connection |
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21 | { |
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22 | /** @var \PDO|null $conn Connection to DB */ |
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23 | protected $conn; |
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24 | |||
25 | |||
26 | /** |
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27 | * Construct for this class |
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28 | * |
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29 | * @access public |
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30 | * |
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31 | * @param IContainer $container |
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32 | * @param array $config |
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33 | * @param array $options |
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34 | * |
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35 | * @result void |
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36 | * @throws Exception |
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37 | */ |
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38 | public function __construct(IContainer $container, array $config = [], array $options = []) |
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55 | |||
56 | /** |
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57 | * Destructor for this class |
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58 | * |
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59 | * @access public |
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60 | * @return void |
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61 | */ |
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62 | public function __destruct() |
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66 | |||
67 | /** |
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68 | * @inheritdoc |
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69 | */ |
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70 | public function rawQuery($query = '', array $params = [], $fetchType = \PDO::FETCH_ASSOC, $fetchClass = 'Model') |
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89 | |||
90 | /** |
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91 | * @inheritdoc |
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92 | */ |
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93 | public function listDatabases() |
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104 | |||
105 | /** |
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106 | * @inheritdoc |
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107 | */ |
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108 | public function infoDatabase($dbName) |
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126 | |||
127 | /** |
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128 | * @inheritdoc |
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129 | */ |
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130 | public function tableExists($table) |
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134 | |||
135 | /** |
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136 | * @inheritdoc |
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137 | */ |
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138 | public function listTables() |
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142 | |||
143 | /** |
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144 | * @inheritdoc |
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145 | */ |
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146 | public function createTable($name, array $elements = [], $params = '') |
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152 | |||
153 | /** |
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154 | * @inheritdoc |
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155 | */ |
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156 | public function clearTable($name) |
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160 | |||
161 | /** |
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162 | * @inheritdoc |
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163 | */ |
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164 | public function removeTable($name) |
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168 | |||
169 | /** |
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170 | * @inheritdoc |
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171 | */ |
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172 | public function fieldExists($field, $table) |
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182 | |||
183 | /** |
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184 | * @inheritdoc |
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185 | */ |
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186 | public function listFields($table) |
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204 | |||
205 | /** |
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206 | * @inheritdoc |
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207 | */ |
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208 | public function fieldInfo($field, $table) |
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214 | |||
215 | /** |
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216 | * @inheritdoc |
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217 | */ |
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218 | public function switchDatabase($dbName) |
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226 | |||
227 | /** |
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228 | * @inheritdoc |
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229 | */ |
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230 | public function insert($table, array $line = [], $multi = false) |
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255 | |||
256 | /** |
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257 | * @inheritdoc |
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258 | */ |
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259 | public function update($table, array $elements = [], $conditions = '') |
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280 | |||
281 | /** |
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282 | * @inheritdoc |
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283 | */ |
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284 | public function delete($table, $conditions, array $ph = []) |
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290 | |||
291 | /** |
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292 | * @inheritdoc |
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293 | */ |
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294 | public function exists($table, array $params = []) |
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308 | |||
309 | /** |
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310 | * @inheritdoc |
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311 | */ |
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312 | public function count($subQuery = '', $table = '') |
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327 | } |
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328 |
This check looks from parameters that have been defined for a function or method, but which are not used in the method body.