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 FilesystemHelper 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 FilesystemHelper, and based on these observations, apply Extract Interface, too.
1 | <?php |
||
24 | class FilesystemHelper { |
||
25 | |||
26 | /** |
||
27 | * Wrapper for filemtime function |
||
28 | * @param string $path |
||
29 | * @return integer |
||
30 | */ |
||
31 | public function filemtime($path){ |
||
34 | |||
35 | /** |
||
36 | * Wrapper for scandir function. |
||
37 | * Filters current and parent directories |
||
38 | * @param string $path |
||
39 | * @return array |
||
40 | */ |
||
41 | public function scandirFiltered($path){ |
||
48 | |||
49 | /** |
||
50 | * Wrapper for scandir function |
||
51 | * @param string $path |
||
52 | * @return array |
||
53 | */ |
||
54 | public function scandir($path){ |
||
57 | |||
58 | /** |
||
59 | * Wrapper for file_exists function |
||
60 | * @param string $path |
||
61 | * @return bool |
||
62 | */ |
||
63 | public function fileExists($path){ |
||
66 | |||
67 | /** |
||
68 | * Wrapper for is_writable function |
||
69 | * @param string $path |
||
70 | * @return bool |
||
71 | */ |
||
72 | public function isWritable($path){ |
||
75 | |||
76 | /** |
||
77 | * Wrapper for is_dir function |
||
78 | * @param string $path |
||
79 | * @return bool |
||
80 | */ |
||
81 | public function isDir($path){ |
||
84 | |||
85 | /** |
||
86 | * Wrapper for md5_file function |
||
87 | * @param string $path |
||
88 | * @return string |
||
89 | */ |
||
90 | public function md5File($path){ |
||
93 | |||
94 | /** |
||
95 | * Wrapper for mkdir |
||
96 | * @param string $path |
||
97 | * @param bool $isRecursive |
||
98 | * @throws \Exception on error |
||
99 | */ |
||
100 | public function mkdir($path, $isRecursive = false){ |
||
105 | |||
106 | /** |
||
107 | * Copy recursive |
||
108 | * @param string $src - source path |
||
109 | * @param string $dest - destination path |
||
110 | * @throws \Exception on error |
||
111 | */ |
||
112 | public function copyr($src, $dest, $stopOnError = true){ |
||
135 | |||
136 | /** |
||
137 | * Moves file/directory |
||
138 | * @param string $src - source path |
||
139 | * @param string $dest - destination path |
||
140 | * @throws \Exception on error |
||
141 | */ |
||
142 | public function move($src, $dest){ |
||
147 | |||
148 | /** |
||
149 | * Check permissions recursive |
||
150 | * @param string $src - path to check |
||
151 | * @param Collection $collection - object to store incorrect permissions |
||
152 | */ |
||
153 | public function checkr($src, $collection){ |
||
172 | |||
173 | /** |
||
174 | * @param string $path |
||
175 | */ |
||
176 | public function removeIfExists($path) { |
||
187 | |||
188 | public function rmdirr($dir) { |
||
206 | |||
207 | /** |
||
208 | * |
||
209 | * @param string $old |
||
210 | * @param string $new |
||
211 | * @param string $temp |
||
212 | * @param string $dirName |
||
213 | */ |
||
214 | public function tripleMove($old, $new, $temp, $dirName){ |
||
224 | |||
225 | } |
||
226 |
If you suppress an error, we recommend checking for the error condition explicitly: