Complex classes like DecimalValue 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 DecimalValue, and based on these observations, apply Extract Interface, too.
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29 | class DecimalValue extends DataValueObject { |
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30 | |||
31 | /** |
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32 | * The $value as a decimal string, in the format described in the class |
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33 | * level documentation of @see DecimalValue, matching @see QUANTITY_VALUE_PATTERN. |
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34 | * |
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35 | * @var string |
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36 | */ |
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37 | private $value; |
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38 | |||
39 | /** |
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40 | * Regular expression for matching decimal strings that conform to the format |
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41 | * described in the class level documentation of @see DecimalValue. |
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42 | */ |
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43 | const QUANTITY_VALUE_PATTERN = '/^[-+]([1-9]\d*|\d)(\.\d+)?\z/'; |
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44 | |||
45 | /** |
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46 | * Constructs a new DecimalValue object, representing the given value. |
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47 | * |
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48 | * @param string|int|float $value If given as a string, the value must match |
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49 | * QUANTITY_VALUE_PATTERN. |
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50 | * |
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51 | * @throws IllegalValueException |
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52 | */ |
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53 | public function __construct( $value ) { |
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78 | |||
79 | /** |
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80 | * Converts the given number to decimal notation. The resulting string conforms to the |
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81 | * rules described in the class level documentation of @see DecimalValue and matches |
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82 | * @see DecimalValue::QUANTITY_VALUE_PATTERN. |
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83 | * |
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84 | * @param int|float $number |
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85 | * |
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86 | * @return string |
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87 | * @throws InvalidArgumentException |
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88 | */ |
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89 | private function convertToDecimal( $number ) { |
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111 | |||
112 | /** |
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113 | * Compares this DecimalValue to another DecimalValue. |
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114 | * |
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115 | * @since 0.1 |
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116 | * |
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117 | * @param self $that |
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118 | * |
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119 | * @throws LogicException |
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120 | * @return int +1 if $this > $that, 0 if $this == $that, -1 if $this < $that |
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121 | */ |
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122 | public function compare( self $that ) { |
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175 | |||
176 | /** |
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177 | * @see Serializable::serialize |
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178 | * |
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179 | * @return string |
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180 | */ |
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181 | public function serialize() { |
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184 | |||
185 | /** |
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186 | * @see Serializable::unserialize |
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187 | * |
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188 | * @param string $data |
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189 | */ |
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190 | public function unserialize( $data ) { |
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193 | |||
194 | /** |
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195 | * @see DataValue::getType |
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196 | * |
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197 | * @return string |
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198 | */ |
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199 | public static function getType() { |
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202 | |||
203 | /** |
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204 | * @see DataValue::getSortKey |
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205 | * |
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206 | * @return float |
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207 | */ |
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208 | public function getSortKey() { |
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211 | |||
212 | /** |
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213 | * Returns the value as a decimal string, using the format described in the class level |
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214 | * documentation of @see DecimalValue and matching @see DecimalValue::QUANTITY_VALUE_PATTERN. |
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215 | * In particular, the string always starts with a sign (either '+' or '-') |
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216 | * and has no leading zeros (except immediately before the decimal point). The decimal point is |
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217 | * optional, but must not be the last character. Trailing zeros are significant. |
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218 | * |
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219 | * @see DataValue::getValue |
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220 | * |
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221 | * @return string |
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222 | */ |
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223 | public function getValue() { |
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226 | |||
227 | /** |
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228 | * Returns the sign of the amount (+ or -). |
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229 | * |
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230 | * @since 0.1 |
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231 | * |
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232 | * @return string "+" or "-". |
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233 | */ |
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234 | public function getSign() { |
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237 | |||
238 | /** |
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239 | * Determines whether this DecimalValue is zero. |
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240 | * |
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241 | * @return bool |
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242 | */ |
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243 | public function isZero() { |
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246 | |||
247 | /** |
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248 | * Returns a new DecimalValue that represents the complement of this DecimalValue. |
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249 | * That is, it constructs a new DecimalValue with the same digits as this, |
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250 | * but with the sign inverted. |
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251 | * |
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252 | * Note that if isZero() returns true, this method returns this |
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253 | * DecimalValue itself (because zero is it's own complement). |
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254 | * |
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255 | * @return self |
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256 | */ |
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257 | public function computeComplement() { |
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268 | |||
269 | /** |
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270 | * Returns a new DecimalValue that represents the absolute (positive) value |
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271 | * of this DecimalValue. That is, it constructs a new DecimalValue with the |
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272 | * same digits as this, but with the positive sign. |
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273 | * |
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274 | * Note that if getSign() returns "+", this method returns this |
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275 | * DecimalValue itself (because a positive value is its own absolute value). |
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276 | * |
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277 | * @return self |
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278 | */ |
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279 | public function computeAbsolute() { |
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286 | |||
287 | /** |
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288 | * Returns the integer part of the value, that is, the part before the decimal point, |
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289 | * without the sign. |
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290 | * |
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291 | * @since 0.1 |
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292 | * |
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293 | * @return string |
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294 | */ |
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295 | public function getIntegerPart() { |
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304 | |||
305 | /** |
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306 | * Returns the fractional part of the value, that is, the part after the decimal point, |
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307 | * if any. |
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308 | * |
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309 | * @since 0.1 |
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310 | * |
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311 | * @return string |
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312 | */ |
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313 | public function getFractionalPart() { |
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322 | |||
323 | /** |
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324 | * Returns the value held by this object, as a float. |
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325 | * Equivalent to floatval( $this->getvalue() ). |
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326 | * |
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327 | * @since 0.1 |
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328 | * |
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329 | * @return float |
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330 | */ |
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331 | public function getValueFloat() { |
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334 | |||
335 | /** |
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336 | * @see DataValue::getArrayValue |
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337 | * |
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338 | * @return string |
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339 | */ |
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340 | public function getArrayValue() { |
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343 | |||
344 | /** |
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345 | * Constructs a new instance of the DataValue from the provided data. |
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346 | * This can round-trip with @see getArrayValue |
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347 | * |
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348 | * @param string|int|float $data |
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349 | * |
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350 | * @return self |
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351 | * @throws IllegalValueException |
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352 | */ |
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353 | public static function newFromArray( $data ) { |
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356 | |||
357 | /** |
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358 | * @return string |
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359 | */ |
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360 | public function __toString() { |
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363 | |||
364 | } |
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365 |