Complex classes like VideoPress_Video 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 VideoPress_Video, and based on these observations, apply Extract Interface, too.
1 | <?php |
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7 | class VideoPress_Video { |
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8 | public $version = 3; |
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9 | |||
10 | /** |
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11 | * Manifest version returned by remote service. |
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12 | * |
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13 | * @var string |
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14 | * @since 1.3 |
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15 | */ |
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16 | const manifest_version = '1.5'; |
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17 | |||
18 | /** |
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19 | * Expiration of the video expressed in Unix time |
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20 | * |
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21 | * @var int |
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22 | * @since 1.3 |
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23 | */ |
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24 | public $expires; |
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25 | |||
26 | /** |
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27 | * VideoPress unique identifier |
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28 | * |
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29 | * @var string |
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30 | * @since 1.3 |
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31 | */ |
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32 | public $guid; |
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33 | |||
34 | /** |
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35 | * WordPress.com blog identifier |
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36 | * |
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37 | * @var int |
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38 | * @since 1.5 |
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39 | */ |
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40 | public $blog_id; |
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41 | |||
42 | /** |
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43 | * Remote blog attachment identifier |
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44 | * |
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45 | * @var int |
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46 | * @since 1.5 |
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47 | */ |
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48 | public $post_id; |
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49 | |||
50 | /** |
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51 | * Maximum desired width. |
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52 | * |
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53 | * @var int |
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54 | * @since 1.3 |
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55 | */ |
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56 | public $maxwidth; |
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57 | |||
58 | /** |
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59 | * Video width calculated based on original video dimensions and the requested maxwidth |
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60 | * |
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61 | * @var int |
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62 | * @since 1.3 |
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63 | */ |
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64 | public $calculated_width; |
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65 | |||
66 | /** |
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67 | * Video height calculated based on original video dimensions and the requested maxwidth |
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68 | * |
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69 | * @var int |
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70 | * @since 1.3 |
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71 | */ |
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72 | public $calculated_height; |
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73 | |||
74 | /** |
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75 | * Video title |
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76 | * |
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77 | * @var string |
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78 | * @since 1.3 |
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79 | */ |
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80 | public $title; |
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81 | |||
82 | /** |
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83 | * Video description |
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84 | * |
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85 | * @var string |
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86 | * @since 4.4 |
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87 | */ |
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88 | public $description; |
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89 | |||
90 | /** |
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91 | * Directionality of title text. ltr or rtl |
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92 | * |
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93 | * @var string |
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94 | * @since 1.3 |
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95 | */ |
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96 | public $text_direction; |
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97 | |||
98 | /** |
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99 | * Text and audio language as ISO 639-2 language code |
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100 | * |
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101 | * @var string |
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102 | * @since 1.3 |
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103 | */ |
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104 | public $language; |
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105 | |||
106 | /** |
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107 | * Video duration in whole seconds |
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108 | * |
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109 | * @var int |
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110 | * @since 1.3 |
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111 | */ |
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112 | public $duration; |
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113 | |||
114 | /** |
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115 | * Recommended minimum age of the viewer. |
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116 | * |
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117 | * @var int |
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118 | * @since 1.3 |
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119 | */ |
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120 | public $age_rating; |
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121 | |||
122 | /** |
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123 | * Video author has restricted video embedding or sharing |
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124 | * |
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125 | * @var bool |
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126 | * @since 1.3 |
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127 | */ |
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128 | public $restricted_embed; |
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129 | |||
130 | /** |
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131 | * Poster frame image URI for the given video guid and calculated dimensions. |
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132 | * |
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133 | * @var string |
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134 | * @since 1.3 |
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135 | */ |
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136 | public $poster_frame_uri; |
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137 | |||
138 | /** |
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139 | * Video files associated with the given guid for the calculated dimensions. |
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140 | * |
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141 | * @var stdClass |
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142 | * @since 1.3 |
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143 | */ |
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144 | public $videos; |
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145 | |||
146 | /** |
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147 | * Video player information |
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148 | * |
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149 | * @var stdClass |
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150 | * @since 1.3 |
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151 | */ |
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152 | public $players; |
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153 | |||
154 | /** |
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155 | * Video player skinning preferences including background color and watermark |
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156 | * |
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157 | * @var array |
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158 | * @since 1.5 |
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159 | */ |
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160 | public $skin; |
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161 | |||
162 | /** |
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163 | * Closed captions if available for the given video. Associative array of ISO 639-2 language code and a WebVTT URI |
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164 | * |
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165 | * @var array |
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166 | * @since 1.5 |
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167 | */ |
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168 | public $captions; |
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169 | |||
170 | /** |
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171 | * Setup the object. |
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172 | * Request video information from VideoPress servers and process the response. |
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173 | * |
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174 | * @since 1.3 |
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175 | * @var string $guid VideoPress unique identifier |
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176 | * @var int $maxwidth maximum requested video width. final width and height are calculated on VideoPress servers based on the aspect ratio of the original video upload. |
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177 | */ |
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178 | public function __construct( $guid, $maxwidth = 640 ) { |
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279 | |||
280 | /** |
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281 | * Convert an Expires HTTP header value into Unix time for use in WP Cache |
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282 | * |
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283 | * @since 1.3 |
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284 | * @var string $expires_header |
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285 | * @return int|bool Unix time or false |
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286 | */ |
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287 | public static function calculate_expiration( $expires_header ) { |
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308 | |||
309 | /** |
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310 | * Extract the site's host domain for statistics and comparison against an allowed site list in the case of restricted embeds. |
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311 | * |
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312 | * @since 1.2 |
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313 | * @param string $url absolute URL |
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314 | * @return bool|string host component of the URL, or false if none found |
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315 | */ |
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316 | public static function hostname( $url ) { |
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319 | |||
320 | |||
321 | /** |
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322 | * Request data from WordPress.com for the given guid, maxwidth, and calculated blog hostname. |
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323 | * |
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324 | * @since 1.3 |
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325 | * @return stdClass|WP_Error parsed JSON response or WP_Error if request unsuccessful |
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326 | */ |
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327 | private function get_data() { |
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375 | } |
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376 |
In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code:
Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: