Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like CommentingController 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 CommentingController, and based on these observations, apply Extract Interface, too.
1 | <?php |
||
25 | class CommentingController extends Controller |
||
26 | { |
||
27 | /** |
||
28 | * {@inheritDoc} |
||
29 | */ |
||
30 | private static $allowed_actions = array( |
||
31 | 'delete', |
||
32 | 'spam', |
||
33 | 'ham', |
||
34 | 'approve', |
||
35 | 'rss', |
||
36 | 'CommentsForm', |
||
37 | 'reply', |
||
38 | 'doPostComment', |
||
39 | 'doPreviewComment' |
||
40 | ); |
||
41 | |||
42 | /** |
||
43 | * {@inheritDoc} |
||
44 | */ |
||
45 | private static $url_handlers = array( |
||
46 | 'reply/$ParentCommentID//$ID/$OtherID' => 'reply', |
||
47 | ); |
||
48 | |||
49 | /** |
||
50 | * Fields required for this form |
||
51 | * |
||
52 | * @var array |
||
53 | * @config |
||
54 | */ |
||
55 | private static $required_fields = array( |
||
56 | 'Name', |
||
57 | 'Email', |
||
58 | 'Comment' |
||
59 | ); |
||
60 | |||
61 | /** |
||
62 | * Parent class this commenting form is for |
||
63 | * |
||
64 | * @var string |
||
65 | */ |
||
66 | private $parentClass = ''; |
||
67 | |||
68 | /** |
||
69 | * The record this commenting form is for |
||
70 | * |
||
71 | * @var DataObject |
||
72 | */ |
||
73 | private $ownerRecord = null; |
||
74 | |||
75 | /** |
||
76 | * Parent controller record |
||
77 | * |
||
78 | * @var Controller |
||
79 | */ |
||
80 | private $ownerController = null; |
||
81 | |||
82 | /** |
||
83 | * Backup url to return to |
||
84 | * |
||
85 | * @var string |
||
86 | */ |
||
87 | protected $fallbackReturnURL = null; |
||
88 | |||
89 | /** |
||
90 | * Set the parent class name to use |
||
91 | * |
||
92 | * @param string $class |
||
93 | */ |
||
94 | public function setParentClass($class) |
||
98 | |||
99 | /** |
||
100 | * Get the parent class name used |
||
101 | * |
||
102 | * @return string |
||
103 | */ |
||
104 | public function getParentClass() |
||
108 | |||
109 | /** |
||
110 | * Encode a fully qualified class name to a URL-safe version |
||
111 | * |
||
112 | * @param string $input |
||
113 | * @return string |
||
114 | */ |
||
115 | public function encodeClassName($input) |
||
119 | |||
120 | /** |
||
121 | * Decode an "encoded" fully qualified class name back to its original |
||
122 | * |
||
123 | * @param string $input |
||
124 | * @return string |
||
125 | */ |
||
126 | public function decodeClassName($input) |
||
130 | |||
131 | /** |
||
132 | * Set the record this controller is working on |
||
133 | * |
||
134 | * @param DataObject $record |
||
135 | */ |
||
136 | public function setOwnerRecord($record) |
||
140 | |||
141 | /** |
||
142 | * Get the record |
||
143 | * |
||
144 | * @return DataObject |
||
145 | */ |
||
146 | public function getOwnerRecord() |
||
150 | |||
151 | /** |
||
152 | * Set the parent controller |
||
153 | * |
||
154 | * @param Controller $controller |
||
155 | */ |
||
156 | public function setOwnerController($controller) |
||
160 | |||
161 | /** |
||
162 | * Get the parent controller |
||
163 | * |
||
164 | * @return Controller |
||
165 | */ |
||
166 | public function getOwnerController() |
||
170 | |||
171 | /** |
||
172 | * Get the commenting option for the current state |
||
173 | * |
||
174 | * @param string $key |
||
175 | * @return mixed Result if the setting is available, or null otherwise |
||
176 | */ |
||
177 | View Code Duplication | public function getOption($key) |
|
192 | |||
193 | /** |
||
194 | * Returns all the commenting options for the current instance. |
||
195 | * |
||
196 | * @return array |
||
197 | */ |
||
198 | View Code Duplication | public function getOptions() |
|
212 | |||
213 | /** |
||
214 | * Workaround for generating the link to this controller |
||
215 | * |
||
216 | * @param string $action |
||
217 | * @param int $id |
||
218 | * @param string $other |
||
219 | * @return string |
||
220 | */ |
||
221 | public function Link($action = '', $id = '', $other = '') |
||
225 | |||
226 | /** |
||
227 | * Outputs the RSS feed of comments |
||
228 | * |
||
229 | * @return HTMLText |
||
230 | */ |
||
231 | public function rss() |
||
235 | |||
236 | /** |
||
237 | * Return an RSSFeed of comments for a given set of comments or all |
||
238 | * comments on the website. |
||
239 | * |
||
240 | * @param HTTPRequest |
||
241 | * |
||
242 | * @return RSSFeed |
||
243 | */ |
||
244 | public function getFeed(HTTPRequest $request) |
||
291 | |||
292 | /** |
||
293 | * Deletes a given {@link Comment} via the URL. |
||
294 | */ |
||
295 | View Code Duplication | public function delete() |
|
314 | |||
315 | /** |
||
316 | * Marks a given {@link Comment} as spam. Removes the comment from display |
||
317 | */ |
||
318 | View Code Duplication | public function spam() |
|
334 | |||
335 | /** |
||
336 | * Marks a given {@link Comment} as ham (not spam). |
||
337 | */ |
||
338 | View Code Duplication | public function ham() |
|
354 | |||
355 | /** |
||
356 | * Marks a given {@link Comment} as approved. |
||
357 | */ |
||
358 | View Code Duplication | public function approve() |
|
373 | |||
374 | /** |
||
375 | * Redirect back to referer if available, ensuring that only site URLs |
||
376 | * are allowed to avoid phishing. If it's an AJAX request render the |
||
377 | * comment in it's new state |
||
378 | */ |
||
379 | private function renderChangedCommentState($comment) |
||
402 | |||
403 | /** |
||
404 | * Returns the comment referenced in the URL (by ID). Permission checking |
||
405 | * should be done in the callee. |
||
406 | * |
||
407 | * @return Comment|false |
||
408 | */ |
||
409 | public function getComment() |
||
423 | |||
424 | /** |
||
425 | * Create a reply form for a specified comment |
||
426 | * |
||
427 | * @param Comment $comment |
||
428 | * @return Form |
||
429 | */ |
||
430 | public function ReplyForm($comment) |
||
449 | |||
450 | |||
451 | /** |
||
452 | * Request handler for reply form. |
||
453 | * |
||
454 | * This method will disambiguate multiple reply forms in the same method |
||
455 | * |
||
456 | * @param HTTPRequest $request |
||
457 | * @throws HTTPResponse_Exception |
||
458 | */ |
||
459 | public function reply(HTTPRequest $request) |
||
470 | |||
471 | /** |
||
472 | * Post a comment form |
||
473 | * |
||
474 | * @return Form |
||
475 | */ |
||
476 | public function CommentsForm() |
||
480 | |||
481 | |||
482 | /** |
||
483 | * @return HTTPResponse|false |
||
484 | */ |
||
485 | public function redirectBack() |
||
519 | } |
||
520 |