Complex classes like WhereStatement 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 WhereStatement, and based on these observations, apply Extract Interface, too.
1 | <?php |
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15 | class WhereStatement extends Statement |
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16 | { |
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17 | /** |
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18 | * @var bool |
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19 | */ |
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20 | protected $having; |
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21 | |||
22 | /** |
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23 | * @var array |
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24 | */ |
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25 | protected $conditions = []; |
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26 | |||
27 | /** |
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28 | * @param bool $having when true, statement becomes a having statement |
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29 | */ |
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30 | public function __construct($having = false) |
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34 | |||
35 | /** |
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36 | * Tells whether this statement is a HAVING statement. |
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37 | * |
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38 | * @return bool true: is HAVING, false: is WHERE |
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39 | */ |
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40 | public function isHaving() |
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44 | |||
45 | /** |
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46 | * Adds a condition to the statement. |
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47 | * |
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48 | * Accepts the following forms: |
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49 | * 1. Equality comparison: |
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50 | * addCondition('username', 'john') |
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51 | * 2. Comparison with custom operator: |
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52 | * addCondition('balance', 100, '>') |
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53 | * 3. IN statement: |
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54 | * addCondition('group', ['admin', 'owner']) |
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55 | * 4. SQL fragment: |
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56 | * addCondition('name LIKE "%john%"') |
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57 | * 5. Subquery: |
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58 | * addCondition(function(SelectQuery $query) {}) |
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59 | * 6. List of conditions to add: |
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60 | * addCondition([['balance', 100, '>'], |
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61 | * ['user_id', 5]]) |
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62 | * 7. Map of equality comparisons: |
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63 | * addCondition(['username' => 'john', |
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64 | * 'user_id' => 5]) |
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65 | * 8. List of SQL fragments: |
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66 | * addCondition(['first_name LIKE "%john%"', |
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67 | * 'last_name LIKE "%doe%"']) |
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68 | * |
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69 | * @param array|string $field |
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70 | * @param string|bool $value condition value (optional) |
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71 | * @param string $operator operator (optional) |
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72 | * |
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73 | * @return self |
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74 | */ |
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75 | public function addCondition($field, $value = false, $operator = '=') |
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114 | |||
115 | /** |
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116 | * Adds an OR condition. Uses same arguments as |
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117 | * adding AND conditions. |
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118 | * |
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119 | * @return self |
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120 | */ |
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121 | public function addOrCondition() |
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127 | |||
128 | /** |
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129 | * Adds a between condition to the query. |
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130 | * |
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131 | * @param string $field |
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132 | * @param mixed $a first between value |
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133 | * @param mixed $b second between value |
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134 | * |
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135 | * @return self |
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136 | */ |
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137 | public function addBetweenCondition($field, $a, $b) |
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143 | |||
144 | /** |
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145 | * Adds a not between condition to the query. |
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146 | * |
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147 | * @param string $field |
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148 | * @param mixed $a first between value |
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149 | * @param mixed $b second between value |
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150 | * |
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151 | * @return self |
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152 | */ |
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153 | public function addNotBetweenCondition($field, $a, $b) |
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159 | |||
160 | /** |
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161 | * Adds an exists condition to the query. |
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162 | * |
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163 | * @param callable $f |
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164 | * |
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165 | * @return self |
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166 | */ |
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167 | public function addExistsCondition(callable $f) |
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173 | |||
174 | /** |
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175 | * Adds a not exists condition to the query. |
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176 | * |
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177 | * @param callable $f |
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178 | * |
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179 | * @return self |
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180 | */ |
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181 | public function addNotExistsCondition(callable $f) |
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187 | |||
188 | /** |
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189 | * Gets the conditions for this statement. |
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190 | * |
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191 | * @return array |
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192 | */ |
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193 | public function getConditions() |
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197 | |||
198 | public function build() |
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218 | |||
219 | /** |
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220 | * Builds a parameterized and escaped SQL fragment |
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221 | * for a condition that uses our own internal |
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222 | * representation. |
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223 | * |
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224 | * A condition is represented by an array, and can be |
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225 | * have one of the following forms: |
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226 | * 1. ['SQL fragment'] |
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227 | * 2. ['identifier', '=', 'value'] |
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228 | * 3. ['BETWEEN', 'identifier', 'value', 'value', true] |
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229 | * 4. ['EXISTS', function(SelectQuery $query) {}, true] |
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230 | * 5. [function(SelectQuery $query) {}] |
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231 | * 6. [function(SelectQuery $query) {}, '=', 'value'] |
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232 | * |
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233 | * @param array $cond |
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234 | * |
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235 | * @return string generated SQL fragment |
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236 | */ |
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237 | protected function buildClause(array $cond) |
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284 | |||
285 | /** |
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286 | * Builds a subquery. |
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287 | * |
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288 | * @param callable $f |
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289 | * |
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290 | * @return string |
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291 | */ |
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292 | protected function buildSubquery(callable $f) |
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302 | |||
303 | /** |
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304 | * Builds an EXISTS clause. |
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305 | * |
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306 | * @param callable $f |
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307 | * @param bool $isExists |
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308 | * |
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309 | * @return string |
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310 | */ |
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311 | protected function buildExists(callable $f, $isExists) |
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317 | |||
318 | /** |
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319 | * Builds a BETWEEN clause. |
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320 | * |
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321 | * @param string $field |
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322 | * @param mixed $value1 |
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323 | * @param mixed $value2 |
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324 | * @param bool $isBetween |
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325 | * |
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326 | * @return string |
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327 | */ |
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328 | protected function buildBetween($field, $value1, $value2, $isBetween) |
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334 | |||
335 | /** |
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336 | * Builds a NULL clause. |
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337 | * |
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338 | * @param string $field |
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339 | * @param bool $isEqual |
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340 | * |
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341 | * @return string |
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342 | */ |
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343 | protected function buildNull($field, $isEqual) |
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349 | |||
350 | /** |
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351 | * Implodes a list of WHERE clauses. |
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352 | * |
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353 | * @param array $clauses |
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354 | * |
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355 | * @return string |
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356 | */ |
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357 | protected function implodeClauses(array $clauses) |
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382 | } |
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383 |
It seems like the type of the argument is not accepted by the function/method which you are calling.
In some cases, in particular if PHP’s automatic type-juggling kicks in this might be fine. In other cases, however this might be a bug.
We suggest to add an explicit type cast like in the following example: