Complex classes like ExpressionVisitor 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 ExpressionVisitor, and based on these observations, apply Extract Interface, too.
1 | <?php |
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12 | class ExpressionVisitor extends ExpressionWalker |
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13 | { |
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14 | final public function walkArray(ArrayExpression $expression) |
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20 | |||
21 | protected function visitArray(ArrayExpression $expression) |
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25 | |||
26 | final public function walkArrayItem(ArrayItemExpression $expression) |
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32 | |||
33 | protected function visitArrayItem(ArrayItemExpression $expression) |
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37 | |||
38 | final public function walkAssignment(AssignmentExpression $expression) |
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44 | |||
45 | protected function visitAssignment(AssignmentExpression $expression) |
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49 | |||
50 | final public function walkBinaryOperation(BinaryOperationExpression $expression) |
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56 | |||
57 | protected function visitBinaryOperation(BinaryOperationExpression $expression) |
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61 | |||
62 | final public function walkCast(CastExpression $expression) |
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68 | |||
69 | protected function visitCast(CastExpression $expression) |
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73 | |||
74 | final public function walkClosure(ClosureExpression $expression) |
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80 | |||
81 | protected function visitClosure(ClosureExpression $expression) |
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85 | |||
86 | final public function walkClosureUsedVariable(ClosureUsedVariableExpression $expression) |
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92 | |||
93 | protected function visitClosureUsedVariable(ClosureUsedVariableExpression $expression) |
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97 | |||
98 | public function walkConstant(ConstantExpression $expression) |
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104 | |||
105 | protected function visitConstant(ConstantExpression $expression) |
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109 | |||
110 | public function walkClassConstant(ClassConstantExpression $expression) |
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116 | |||
117 | protected function visitClassConstant(ClassConstantExpression $expression) |
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121 | |||
122 | final public function walkParameter(ParameterExpression $expression) |
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128 | |||
129 | protected function visitParameter(ParameterExpression $expression) |
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133 | |||
134 | final public function walkArgument(ArgumentExpression $expression) |
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135 | { |
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136 | $this->visitArgument($expression); |
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137 | |||
138 | return $expression; |
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139 | } |
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140 | |||
141 | protected function visitArgument(ArgumentExpression $expression) |
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142 | { |
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143 | |||
144 | } |
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145 | |||
146 | final public function walkEmpty(EmptyExpression $expression) |
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152 | |||
153 | protected function visitEmpty(EmptyExpression $expression) |
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157 | |||
158 | final public function walkIsset(IssetExpression $expression) |
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164 | |||
165 | protected function visitIsset(IssetExpression $expression) |
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169 | |||
170 | final public function walkUnset(UnsetExpression $expression) |
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176 | |||
177 | protected function visitUnset(UnsetExpression $expression) |
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181 | |||
182 | final public function walkField(FieldExpression $expression) |
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188 | |||
189 | protected function visitField(FieldExpression $expression) |
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193 | |||
194 | final public function walkFunctionCall(FunctionCallExpression $expression) |
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200 | |||
201 | protected function visitFunctionCall(FunctionCallExpression $expression) |
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205 | |||
206 | final public function walkIndex(IndexExpression $expression) |
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212 | |||
213 | protected function visitIndex(IndexExpression $expression) |
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217 | |||
218 | final public function walkInvocation(InvocationExpression $expression) |
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224 | |||
225 | protected function visitInvocation(InvocationExpression $expression) |
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229 | |||
230 | final public function walkMethodCall(MethodCallExpression $expression) |
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236 | |||
237 | protected function visitMethodCall(MethodCallExpression $expression) |
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241 | |||
242 | final public function walkNew(NewExpression $expression) |
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248 | |||
249 | protected function visitNew(NewExpression $expression) |
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253 | |||
254 | final public function walkReturn(ReturnExpression $expression) |
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260 | |||
261 | protected function visitReturn(ReturnExpression $expression) |
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265 | |||
266 | final public function walkThrow(ThrowExpression $expression) |
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272 | |||
273 | protected function visitThrow(ThrowExpression $expression) |
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277 | |||
278 | final public function walkStaticMethodCall(StaticMethodCallExpression $expression) |
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284 | |||
285 | protected function visitStaticMethodCall(StaticMethodCallExpression $expression) |
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289 | |||
290 | final public function walkStaticField(StaticFieldExpression $expression) |
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296 | |||
297 | protected function visitStaticField(StaticFieldExpression $expression) |
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301 | |||
302 | final public function walkTernary(TernaryExpression $expression) |
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308 | |||
309 | protected function visitTernary(TernaryExpression $expression) |
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313 | |||
314 | final public function walkUnaryOperation(UnaryOperationExpression $expression) |
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320 | |||
321 | protected function visitUnaryOperation(UnaryOperationExpression $expression) |
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325 | |||
326 | final public function walkValue(ValueExpression $expression) |
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332 | |||
333 | protected function visitValue(ValueExpression $expression) |
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337 | |||
338 | final public function walkVariable(VariableExpression $expression) |
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344 | |||
345 | protected function visitVariable(VariableExpression $expression) |
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349 | } |
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350 |