Complex classes like Transaction 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 Transaction, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 14 | class Transaction extends Serializable implements TransactionInterface  | 
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| 15 | { | 
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| 16 | /**  | 
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| 17 | * @var int  | 
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| 18 | */  | 
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| 19 | private $version;  | 
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| 20 | |||
| 21 | /**  | 
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| 22 | * @var TransactionInputInterface[]  | 
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| 23 | */  | 
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| 24 | private $inputs;  | 
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| 25 | |||
| 26 | /**  | 
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| 27 | * @var TransactionOutputInterface[]  | 
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| 28 | */  | 
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| 29 | private $outputs;  | 
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| 30 | |||
| 31 | /**  | 
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| 32 | * @var ScriptWitnessInterface[]  | 
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| 33 | */  | 
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| 34 | private $witness;  | 
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| 35 | |||
| 36 | /**  | 
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| 37 | * @var int  | 
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| 38 | */  | 
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| 39 | private $lockTime;  | 
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| 40 | |||
| 41 | /**  | 
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| 42 | * Transaction constructor.  | 
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| 43 | *  | 
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| 44 | * @param int $nVersion  | 
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| 45 | * @param TransactionInputInterface[] $vin  | 
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| 46 | * @param TransactionOutputInterface[] $vout  | 
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| 47 | * @param ScriptWitnessInterface[] $vwit  | 
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| 48 | * @param int $nLockTime  | 
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| 49 | */  | 
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| 50 | 5000 | public function __construct(  | 
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| 51 | $nVersion = TransactionInterface::DEFAULT_VERSION,  | 
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| 52 | array $vin = [],  | 
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| 53 | array $vout = [],  | 
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| 54 | array $vwit = [],  | 
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| 55 | $nLockTime = 0  | 
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| 56 |     ) { | 
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| 57 | 5000 |         if ($nVersion > TransactionInterface::MAX_VERSION) { | 
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| 58 | 6 |             throw new \InvalidArgumentException('Version must be less than ' . TransactionInterface::MAX_VERSION); | 
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| 59 | }  | 
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| 60 | |||
| 61 | 4994 |         if ($nLockTime < 0 || $nLockTime > TransactionInterface::MAX_LOCKTIME) { | 
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| 62 | 6 |             throw new \InvalidArgumentException('Locktime must be positive and less than ' . TransactionInterface::MAX_LOCKTIME); | 
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| 63 | }  | 
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| 64 | |||
| 65 | 4988 | $this->version = $nVersion;  | 
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| 66 | 4988 | $this->lockTime = $nLockTime;  | 
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| 67 | |||
| 68 |         $this->inputs = array_map(function (TransactionInputInterface $input) { | 
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| 69 | 4784 | return $input;  | 
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| 70 | 4988 | }, $vin);  | 
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| 71 |         $this->outputs = array_map(function (TransactionOutputInterface $output) { | 
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| 72 | 4808 | return $output;  | 
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| 73 | 4988 | }, $vout);  | 
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| 74 | 4988 |         $this->witness = array_map(function (ScriptWitnessInterface $scriptWitness) { | 
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| 75 | 4472 | return $scriptWitness;  | 
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| 76 | 4988 | }, $vwit);  | 
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| 77 | 4988 | }  | 
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| 78 | |||
| 79 | /**  | 
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| 80 | * @return Transaction  | 
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| 81 | */  | 
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| 82 | 308 | public function __clone()  | 
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| 83 |     { | 
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| 84 | //$this->inputs = clone $this->inputs;  | 
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| 85 | //$this->outputs = clone $this->outputs;  | 
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| 86 | 308 | }  | 
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| 87 | |||
| 88 | /**  | 
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| 89 | * @return BufferInterface  | 
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| 90 | */  | 
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| 91 | 4508 | public function getTxHash()  | 
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| 95 | |||
| 96 | /**  | 
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| 97 | * @return BufferInterface  | 
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| 98 | */  | 
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| 99 | 4508 | public function getTxId()  | 
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| 103 | |||
| 104 | /**  | 
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| 105 | * @return BufferInterface  | 
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| 106 | */  | 
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| 107 | public function getWitnessTxId()  | 
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| 111 | |||
| 112 | /**  | 
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| 113 | * @return int  | 
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| 114 | */  | 
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| 115 | 4718 | public function getVersion()  | 
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| 119 | |||
| 120 | /**  | 
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| 121 | * Get the array of inputs in the transaction  | 
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| 122 | *  | 
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| 123 | * @return TransactionInputInterface[]  | 
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| 124 | */  | 
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| 125 | 4700 | public function getInputs()  | 
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| 129 | |||
| 130 | /**  | 
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| 131 | * @param int $index  | 
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| 132 | * @return TransactionInputInterface  | 
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| 133 | */  | 
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| 134 | 218 | public function getInput($index)  | 
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| 135 |     { | 
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| 136 | 218 |         if (!isset($this->inputs[$index])) { | 
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| 137 | 6 |             throw new \RuntimeException('No input at this index'); | 
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| 138 | }  | 
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| 139 | 212 | return $this->inputs[$index];  | 
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| 140 | }  | 
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| 141 | |||
| 142 | /**  | 
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| 143 | * Get Outputs  | 
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| 144 | *  | 
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| 145 | * @return TransactionOutputInterface[]  | 
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| 146 | */  | 
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| 147 | 4742 | public function getOutputs()  | 
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| 151 | |||
| 152 | /**  | 
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| 153 | * @param int $vout  | 
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| 154 | * @return TransactionOutputInterface  | 
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| 155 | */  | 
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| 156 | 4502 | public function getOutput($vout)  | 
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| 163 | |||
| 164 | /**  | 
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| 165 | * @return bool  | 
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| 166 | */  | 
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| 167 | public function hasWitness()  | 
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| 177 | |||
| 178 | /**  | 
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| 179 | * @return ScriptWitnessInterface[]  | 
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| 180 | */  | 
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| 181 | 296 | public function getWitnesses()  | 
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| 185 | |||
| 186 | /**  | 
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| 187 | * @return ScriptWitnessInterface  | 
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| 188 | */  | 
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| 189 | public function getWitness($index)  | 
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| 196 | |||
| 197 | /**  | 
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| 198 | * @param int $vout  | 
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| 199 | * @return OutPointInterface  | 
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| 200 | */  | 
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| 201 | 4412 | public function makeOutpoint($vout)  | 
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| 206 | |||
| 207 | /**  | 
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| 208 | * @param int $vout  | 
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| 209 | * @return Utxo  | 
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| 210 | */  | 
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| 211 | public function makeUtxo($vout)  | 
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| 215 | |||
| 216 | /**  | 
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| 217 | * Get Lock Time  | 
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| 218 | *  | 
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| 219 | * @return int  | 
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| 220 | */  | 
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| 221 | 4724 | public function getLockTime()  | 
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| 225 | |||
| 226 | /**  | 
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| 227 | * @return int|string  | 
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| 228 | */  | 
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| 229 | 6 | public function getValueOut()  | 
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| 239 | |||
| 240 | /**  | 
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| 241 | * @return bool  | 
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| 242 | */  | 
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| 243 | 6 | public function isCoinbase()  | 
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| 247 | |||
| 248 | /**  | 
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| 249 | * @param TransactionInterface $tx  | 
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| 250 | * @return bool  | 
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| 251 | */  | 
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| 252 | 6 | public function equals(TransactionInterface $tx)  | 
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| 286 | |||
| 287 | /**  | 
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| 288 | * @return Validator  | 
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| 289 | */  | 
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| 290 | 54 | public function validator()  | 
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| 294 | |||
| 295 | /**  | 
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| 296 | * @return BufferInterface  | 
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| 297 | */  | 
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| 298 | 4613 | public function getBuffer()  | 
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| 302 | |||
| 303 | /**  | 
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| 304 | * @return BufferInterface  | 
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| 305 | */  | 
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| 306 | 54 | public function getWitnessBuffer()  | 
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| 310 | }  | 
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| 311 | 
If a method or function can return multiple different values and unless you are sure that you only can receive a single value in this context, we recommend to add an additional type check:
If this a common case that PHP Analyzer should handle natively, please let us know by opening an issue.