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 Connection 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 Connection, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 32 | class Connection extends ClientConnection implements CommandInterface |
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| 33 | { |
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| 34 | |||
| 35 | /** |
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| 36 | * The AMQP protocol header is sent by the client before any frame-based |
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| 37 | * communication takes place. It is the only data transferred that is not |
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| 38 | * a frame. |
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| 39 | */ |
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| 40 | const PROTOCOL_HEADER = "AMQP\x00\x00\x09\x01"; |
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| 41 | |||
| 42 | /** |
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| 43 | * The maximum number of channels. |
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| 44 | * |
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| 45 | * AMQP channel ID is 2 bytes, but zero is reserved for connection-level |
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| 46 | * communication. |
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| 47 | */ |
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| 48 | const MAXIMUM_CHANNELS = 0xffff - 1; |
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| 49 | |||
| 50 | /** |
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| 51 | * The maximum frame size the client supports. |
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| 52 | * |
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| 53 | * Note: RabbitMQ's default is 0x20000 (128 KB), our limit is higher to |
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| 54 | * allow for some server-side configurability. |
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| 55 | */ |
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| 56 | const MAXIMUM_FRAME_SIZE = 0x80000; // 512 KB |
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| 57 | |||
| 58 | /** |
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| 59 | * The broker sends channelMax of zero in the tune frame if it does not |
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| 60 | * impose a channel limit. |
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| 61 | */ |
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| 62 | const UNLIMITED_CHANNELS = 0; |
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| 63 | |||
| 64 | /** |
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| 65 | * The broker sends frameMax of zero in the tune frame if it does not impose |
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| 66 | * a frame size limit. |
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| 67 | */ |
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| 68 | const UNLIMITED_FRAME_SIZE = 0; |
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| 69 | |||
| 70 | /** |
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| 71 | * The broker sends a heartbeat of zero in the tune frame if it does not use |
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| 72 | * heartbeats. |
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| 73 | */ |
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| 74 | const HEARTBEAT_DISABLED = 0; |
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| 75 | |||
| 76 | /** |
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| 77 | * Event raised when protocol handshake ready |
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| 78 | */ |
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| 79 | const EVENT_ON_HANDSHAKE = 'event.amqp.connection.handshake'; |
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| 80 | |||
| 81 | /** |
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| 82 | * Event raised when connection close frame incoming |
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| 83 | */ |
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| 84 | |||
| 85 | const EVENT_ON_CONNECTION_CLOSE = 'event.amqp.connection.close'; |
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| 86 | |||
| 87 | /** |
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| 88 | * @var FrameParser |
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| 89 | */ |
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| 90 | protected $parser; |
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| 91 | |||
| 92 | /** |
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| 93 | * @var FrameSerializer |
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| 94 | */ |
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| 95 | protected $serializer; |
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| 96 | |||
| 97 | /** |
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| 98 | * @var ConnectionOptions |
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| 99 | */ |
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| 100 | protected $connectionOptions; |
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| 101 | |||
| 102 | /** |
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| 103 | * @var bool |
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| 104 | */ |
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| 105 | protected $isHandshaked = false; |
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| 106 | |||
| 107 | /** |
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| 108 | * The broker's supported features. |
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| 109 | * @var Features |
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| 110 | */ |
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| 111 | private $features; |
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| 112 | |||
| 113 | /** |
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| 114 | * @var int |
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| 115 | */ |
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| 116 | private $maximumChannelCount; |
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| 117 | |||
| 118 | /** |
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| 119 | * @var int |
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| 120 | */ |
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| 121 | private $maximumFrameSize; |
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| 122 | |||
| 123 | /** |
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| 124 | * @var array |
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| 125 | */ |
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| 126 | private $channels = []; |
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| 127 | |||
| 128 | /** |
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| 129 | * @var int |
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| 130 | */ |
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| 131 | private $nextChannelId = 1; |
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| 132 | |||
| 133 | /** |
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| 134 | * @var bool |
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| 135 | */ |
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| 136 | private $debug = false; |
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| 137 | |||
| 138 | /** |
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| 139 | * |
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| 140 | */ |
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| 141 | protected function init() |
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| 156 | |||
| 157 | /** |
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| 158 | * |
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| 159 | */ |
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| 160 | public function onReady() |
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| 170 | |||
| 171 | /** |
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| 172 | * |
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| 173 | * @throws \PHPDaemon\Clients\AMQP\Driver\Protocol\Exception\AMQPProtocolException |
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| 174 | * @throws \PHPDaemon\Clients\AMQP\Driver\Exception\AMQPConnectionException |
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| 175 | * @throws \InvalidArgumentException |
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| 176 | */ |
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| 177 | protected function onRead() |
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| 359 | |||
| 360 | /** |
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| 361 | * @param int $id |
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| 362 | * @param callable $callback |
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| 363 | * @throws \InvalidArgumentException |
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| 364 | * @throws \PHPDaemon\Clients\AMQP\Driver\Protocol\Exception\AMQPProtocolException |
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| 365 | * @throws \PHPDaemon\Clients\AMQP\Driver\Exception\AMQPConnectionException |
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| 366 | */ |
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| 367 | public function getChannel(callable $callback, $id = 1) |
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| 378 | |||
| 379 | /** |
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| 380 | * @param callable|null $callback |
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| 381 | * @throws \InvalidArgumentException |
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| 382 | * @throws \PHPDaemon\Clients\AMQP\Driver\Protocol\Exception\AMQPProtocolException |
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| 383 | * @throws \PHPDaemon\Clients\AMQP\Driver\Exception\AMQPConnectionException |
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| 384 | */ |
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| 385 | public function openChannel(callable $callback = null) |
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| 389 | |||
| 390 | /** |
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| 391 | * @return int |
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| 392 | * @throws \PHPDaemon\Clients\AMQP\Driver\Exception\AMQPConnectionException |
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| 393 | */ |
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| 394 | public function findChannelId() |
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| 424 | |||
| 425 | /** |
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| 426 | * @param OutgoingFrame $frame |
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| 427 | * @param callable|null $callback |
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| 428 | * @return bool |
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| 429 | * @throws \PHPDaemon\Clients\AMQP\Driver\Protocol\Exception\AMQPProtocolException |
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| 430 | * @throws \InvalidArgumentException |
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| 431 | */ |
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| 432 | public function command(OutgoingFrame $frame, callable $callback = null) |
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| 440 | |||
| 441 | |||
| 442 | public function addChannel($id, Channel $channel) |
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| 448 | |||
| 449 | /** |
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| 450 | * @return Features |
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| 451 | */ |
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| 452 | public function getFeatures() |
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| 456 | |||
| 457 | /** |
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| 458 | * @return ConnectionOptions |
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| 459 | */ |
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| 460 | public function getConnectionOptions() |
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| 464 | |||
| 465 | /** |
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| 466 | * @return int |
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| 467 | */ |
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| 468 | public function getMaximumChannelCount() |
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| 472 | |||
| 473 | /** |
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| 474 | * @return int |
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| 475 | */ |
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| 476 | public function getMaximumFrameSize() |
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| 480 | |||
| 481 | /** |
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| 482 | * @return bool |
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| 483 | */ |
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| 484 | public function isHandshaked() |
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| 488 | } |
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| 489 |
Overly long lines are hard to read on any screen. Most code styles therefor impose a maximum limit on the number of characters in a line.