Complex classes like GraphPrinter 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 GraphPrinter, and based on these observations, apply Extract Interface, too.
1 | <?php |
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23 | class GraphPrinter extends SMWResultPrinter { |
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24 | |||
25 | const NODELABEL_DISPLAYTITLE = 'displaytitle'; |
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26 | |||
27 | public static $NODE_LABELS = [ |
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28 | self::NODELABEL_DISPLAYTITLE, |
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29 | ]; |
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30 | |||
31 | public static $NODE_SHAPES = [ |
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32 | 'box', |
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33 | 'box3d', |
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34 | 'circle', |
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35 | 'component', |
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36 | 'diamond', |
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37 | 'doublecircle', |
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38 | 'doubleoctagon', |
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39 | 'egg', |
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40 | 'ellipse', |
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41 | 'folder', |
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42 | 'hexagon', |
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43 | 'house', |
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44 | 'invhouse', |
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45 | 'invtrapezium', |
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46 | 'invtriangle', |
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47 | 'Mcircle', |
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48 | 'Mdiamond', |
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49 | 'Msquare', |
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50 | 'none', |
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51 | 'note', |
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52 | 'octagon', |
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53 | 'parallelogram', |
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54 | 'pentagon ', |
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55 | 'plaintext', |
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56 | 'point', |
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57 | 'polygon', |
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58 | 'rect', |
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59 | 'rectangle', |
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60 | 'septagon', |
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61 | 'square', |
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62 | 'tab', |
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63 | 'trapezium', |
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64 | 'triangle', |
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65 | 'tripleoctagon', |
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66 | ]; |
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67 | |||
68 | protected $m_graphName; |
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69 | protected $m_graphLabel; |
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70 | protected $m_graphColor; |
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71 | protected $m_graphLegend; |
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72 | protected $m_graphLink; |
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73 | protected $m_rankdir; |
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74 | protected $m_graphSize; |
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75 | protected $m_labelArray = []; |
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76 | protected $m_graphColors = [ |
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77 | 'black', |
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78 | 'red', |
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79 | 'green', |
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80 | 'blue', |
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81 | 'darkviolet', |
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82 | 'gold', |
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83 | 'deeppink', |
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84 | 'brown', |
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85 | 'bisque', |
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86 | 'darkgreen', |
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87 | 'yellow', |
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88 | 'darkblue', |
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89 | 'magenta', |
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90 | 'steelblue2' ]; |
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91 | protected $m_nameProperty; |
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92 | protected $m_nodeShape; |
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93 | protected $m_parentRelation; |
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94 | protected $m_wordWrapLimit; |
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95 | protected $m_nodeLabel; |
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96 | |||
97 | /** |
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98 | * (non-PHPdoc) |
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99 | * @see SMWResultPrinter::handleParameters() |
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100 | */ |
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101 | protected function handleParameters( array $params, $outputmode ) { |
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124 | |||
125 | protected function getResultText( SMWQueryResult $res, $outputmode ) { |
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175 | |||
176 | /** |
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177 | * Returns the GV for a single subject. |
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178 | * |
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179 | * @since 1.5.4 |
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180 | * |
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181 | * @param array $row |
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182 | * @param $outputmode |
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183 | * |
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184 | * @return string |
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185 | */ |
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186 | protected function getGVForItem( array /* of SMWResultArray */ |
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210 | |||
211 | /** |
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212 | * Returns the GV for a single SMWDataValue. |
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213 | * |
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214 | * @since 1.5.4 |
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215 | * |
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216 | * @param SMWDataValue $object |
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217 | * @param $outputmode |
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218 | * @param boolean $isName Is this the name that should be used for the node? |
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219 | * @param string $name |
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220 | * @param string $labelName |
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221 | * |
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222 | * @return string |
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223 | */ |
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224 | protected function getGVForDataValue( SMWDataValue $object, $outputmode, $isName, $name, $labelName ) { |
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282 | |||
283 | /** |
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284 | * Returns the word wrapped version of the provided text. |
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285 | * |
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286 | * @since 1.5.4 |
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287 | * |
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288 | * @param string $text |
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289 | * @param integer $charLimit |
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290 | * |
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291 | * @return string |
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292 | */ |
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293 | protected function getWordWrappedText( $text, $charLimit ) { |
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319 | |||
320 | /** |
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321 | * (non-PHPdoc) |
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322 | * @see SMWResultPrinter::getName() |
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323 | */ |
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324 | public function getName() { |
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327 | |||
328 | /** |
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329 | * @see SMWResultPrinter::getParamDefinitions |
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330 | * |
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331 | * @since 1.8 |
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332 | * |
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333 | * @param $definitions array of IParamDefinition |
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334 | * |
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335 | * @return array of IParamDefinition|array |
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336 | */ |
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337 | public function getParamDefinitions( array $definitions ) { |
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418 | |||
419 | } |
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420 |
If you define a variable conditionally, it can happen that it is not defined for all execution paths.
Let’s take a look at an example:
In the above example, the variable $x is defined if you pass “foo” or “bar” as argument for $a. However, since the switch statement has no default case statement, if you pass any other value, the variable $x would be undefined.
Available Fixes
Check for existence of the variable explicitly:
Define a default value for the variable:
Add a value for the missing path: