Complex classes like Router 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 Router, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 13 | class Router implements |
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| 14 | InjectionAwareInterface, |
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| 15 | ConfigureInterface |
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| 16 | { |
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| 17 | use InjectionAwareTrait; |
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| 18 | use Configure2Trait { |
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| 19 | configure as protected configure2; |
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| 20 | } |
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| 21 | |||
| 22 | |||
| 23 | |||
| 24 | /** |
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| 25 | * @var array $routes all the routes. |
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| 26 | * @var array $internalRoutes all internal routes. |
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| 27 | * @var null|string $lastRoute last route that was matched and called. |
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| 28 | */ |
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| 29 | private $routes = []; |
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| 30 | private $internalRoutes = []; |
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| 31 | private $lastRoute = null; |
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| 32 | |||
| 33 | |||
| 34 | |||
| 35 | /** |
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| 36 | * Load and apply configurations. |
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| 37 | * |
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| 38 | * @param array|string $what is an array with key/value config options |
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| 39 | * or a file to be included which returns such |
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| 40 | * an array. |
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| 41 | * |
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| 42 | * @return self |
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| 43 | */ |
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| 44 | public function configure($what) |
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| 72 | |||
| 73 | |||
| 74 | |||
| 75 | /** |
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| 76 | * Handle the routes and match them towards the request, dispatch them |
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| 77 | * when a match is made. Each route handler may throw exceptions that |
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| 78 | * may redirect to an internal route for error handling. |
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| 79 | * Several routes can match and if the routehandler does not break |
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| 80 | * execution flow, the route matching will carry on. |
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| 81 | * Only the last routehandler will get its return value returned further. |
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| 82 | * |
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| 83 | * @param string $path the path to find a matching handler for. |
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| 84 | * @param string $method the request method to match. |
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| 85 | * |
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| 86 | * @return mixed content returned from route. |
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| 87 | */ |
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| 88 | public function handle($path, $method = null) |
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| 113 | |||
| 114 | |||
| 115 | |||
| 116 | /** |
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| 117 | * Handle an internal route, the internal routes are not exposed to the |
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| 118 | * end user. |
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| 119 | * |
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| 120 | * @param string $rule for this route. |
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| 121 | * |
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| 122 | * @return void |
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| 123 | * |
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| 124 | * @throws \Anax\Route\NotFoundException |
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| 125 | */ |
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| 126 | public function handleInternal($rule) |
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| 135 | |||
| 136 | |||
| 137 | |||
| 138 | /** |
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| 139 | * Load routes from a config file, the file should return an array with |
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| 140 | * details of the routes. These details are used to create the routes. |
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| 141 | * |
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| 142 | * @param array $route details on the route. |
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| 143 | * |
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| 144 | * @return self |
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| 145 | */ |
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| 146 | public function load($route) |
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| 183 | |||
| 184 | |||
| 185 | |||
| 186 | /** |
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| 187 | * Add a route with a request method, a path rule to match and an action |
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| 188 | * as the callback. Adding several path rules (array) results in several |
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| 189 | * routes being created. |
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| 190 | * |
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| 191 | * @param null|string|array $method as a valid request method. |
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| 192 | * @param null|string|array $rule path rule for this route. |
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| 193 | * @param null|string|callable $action to implement a handler for the route. |
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| 194 | * @param null|string $info about the route. |
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| 195 | * |
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| 196 | * @return class|array as new route(s), class if one added, else array. |
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| 197 | */ |
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| 198 | public function any($method, $rule, $action, $info = null) |
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| 212 | |||
| 213 | |||
| 214 | |||
| 215 | /** |
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| 216 | * Add a route to the router by rule(s) and a callback. |
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| 217 | * |
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| 218 | * @param null|string|array $rule for this route. |
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| 219 | * @param null|string|callable $action a callback handler for the route. |
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| 220 | * |
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| 221 | * @return class|array as new route(s), class if one added, else array. |
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| 222 | */ |
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| 223 | public function add($rule, $action = null) |
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| 227 | |||
| 228 | |||
| 229 | |||
| 230 | /** |
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| 231 | * Add a default route which will be applied for any path. |
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| 232 | * |
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| 233 | * @param string|callable $action a callback handler for the route. |
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| 234 | * |
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| 235 | * @return class as new route. |
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| 236 | */ |
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| 237 | public function always($action) |
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| 241 | |||
| 242 | |||
| 243 | |||
| 244 | /** |
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| 245 | * Add a default route which will be applied for any path, if the choosen |
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| 246 | * request method is matching. |
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| 247 | * |
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| 248 | * @param null|string|array $method as request methods |
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| 249 | * @param null|string|callable $action a callback handler for the route. |
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| 250 | * |
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| 251 | * @return class|array as new route(s), class if one added, else array. |
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| 252 | */ |
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| 253 | public function all($method, $action) |
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| 257 | |||
| 258 | |||
| 259 | |||
| 260 | /** |
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| 261 | * Shortcut to add a GET route. |
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| 262 | * |
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| 263 | * @param null|string|array $method as request methods |
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| 264 | * @param null|string|callable $action a callback handler for the route. |
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| 265 | * |
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| 266 | * @return class|array as new route(s), class if one added, else array. |
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| 267 | */ |
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| 268 | public function get($rule, $action) |
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| 272 | |||
| 273 | |||
| 274 | |||
| 275 | /** |
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| 276 | * Shortcut to add a POST route. |
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| 277 | * |
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| 278 | * @param null|string|array $method as request methods |
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| 279 | * @param null|string|callable $action a callback handler for the route. |
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| 280 | * |
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| 281 | * @return class|array as new route(s), class if one added, else array. |
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| 282 | */ |
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| 283 | public function post($rule, $action) |
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| 287 | |||
| 288 | |||
| 289 | |||
| 290 | /** |
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| 291 | * Shortcut to add a PUT route. |
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| 292 | * |
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| 293 | * @param null|string|array $method as request methods |
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| 294 | * @param null|string|callable $action a callback handler for the route. |
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| 295 | * |
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| 296 | * @return class|array as new route(s), class if one added, else array. |
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| 297 | */ |
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| 298 | public function put($rule, $action) |
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| 302 | |||
| 303 | |||
| 304 | |||
| 305 | /** |
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| 306 | * Shortcut to add a DELETE route. |
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| 307 | * |
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| 308 | * @param null|string|array $method as request methods |
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| 309 | * @param null|string|callable $action a callback handler for the route. |
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| 310 | * |
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| 311 | * @return class|array as new route(s), class if one added, else array. |
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| 312 | */ |
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| 313 | public function delete($rule, $action) |
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| 317 | |||
| 318 | |||
| 319 | |||
| 320 | /** |
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| 321 | * Add an internal route to the router, this route is not exposed to the |
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| 322 | * browser and the end user. |
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| 323 | * |
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| 324 | * @param string $rule for this route |
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| 325 | * @param null|string|callable $action a callback handler for the route. |
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| 326 | * |
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| 327 | * @return class|array as new route(s), class if one added, else array. |
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| 328 | */ |
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| 329 | public function addInternal($rule, $action) |
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| 336 | |||
| 337 | |||
| 338 | |||
| 339 | /** |
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| 340 | * Get the route for the last route that was handled. |
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| 341 | * |
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| 342 | * @return mixed |
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| 343 | */ |
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| 344 | public function getLastRoute() |
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| 348 | |||
| 349 | |||
| 350 | |||
| 351 | /** |
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| 352 | * Get all routes. |
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| 353 | * |
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| 354 | * @return array with all routes. |
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| 355 | */ |
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| 356 | public function getAll() |
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| 360 | |||
| 361 | |||
| 362 | |||
| 363 | /** |
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| 364 | * Get all internal routes. |
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| 365 | * |
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| 366 | * @return array with internal routes. |
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| 367 | */ |
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| 368 | public function getInternal() |
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| 372 | } |
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| 373 |
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: