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 DatabaseTrait 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 DatabaseTrait, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
||
| 12 | trait DatabaseTrait |
||
| 13 | { |
||
| 14 | /** |
||
| 15 | * Returns the current default_with_oids setting. |
||
| 16 | * |
||
| 17 | * @return string default_with_oids setting |
||
| 18 | */ |
||
| 19 | public function getDefaultWithOid() |
||
| 25 | |||
| 26 | /** |
||
| 27 | * Determines whether or not a user is a super user. |
||
| 28 | * |
||
| 29 | * @param string $username The username of the user |
||
| 30 | * |
||
| 31 | * @return bool true if is a super user, false otherwise |
||
| 32 | */ |
||
| 33 | public function isSuperUser($username = '') |
||
| 53 | |||
| 54 | /** |
||
| 55 | * Analyze a database. |
||
| 56 | * |
||
| 57 | * @param string $table (optional) The table to analyze |
||
| 58 | * |
||
| 59 | * @return bool 0 if successful |
||
| 60 | */ |
||
| 61 | public function analyzeDB($table = '') |
||
| 75 | |||
| 76 | /** |
||
| 77 | * Return all information about a particular database. |
||
| 78 | * |
||
| 79 | * @param string $database The name of the database to retrieve |
||
| 80 | * |
||
| 81 | * @return \PHPPgAdmin\ADORecordSet The database info |
||
| 82 | */ |
||
| 83 | public function getDatabase($database) |
||
| 90 | |||
| 91 | /** |
||
| 92 | * Return all database available on the server. |
||
| 93 | * |
||
| 94 | * @param null|string $currentdatabase database name that should be on top of the resultset |
||
| 95 | * |
||
| 96 | * @return \PHPPgAdmin\ADORecordSet A list of databases, sorted alphabetically |
||
| 97 | */ |
||
| 98 | public function getDatabases($currentdatabase = null) |
||
| 158 | |||
| 159 | /** |
||
| 160 | * Return the database comment of a db from the shared description table. |
||
| 161 | * |
||
| 162 | * @param string $database the name of the database to get the comment for |
||
| 163 | * |
||
| 164 | * @return \PHPPgAdmin\ADORecordSet recordset of the db comment info |
||
| 165 | */ |
||
| 166 | public function getDatabaseComment($database) |
||
| 177 | |||
| 178 | /** |
||
| 179 | * Return the database owner of a db. |
||
| 180 | * |
||
| 181 | * @param string $database the name of the database to get the owner for |
||
| 182 | * |
||
| 183 | * @return \PHPPgAdmin\ADORecordSet recordset of the db owner info |
||
| 184 | */ |
||
| 185 | public function getDatabaseOwner($database) |
||
| 192 | |||
| 193 | // Help functions |
||
| 194 | |||
| 195 | // Database functions |
||
| 196 | |||
| 197 | /** |
||
| 198 | * Returns the current database encoding. |
||
| 199 | * |
||
| 200 | * @return string The encoding. eg. SQL_ASCII, UTF-8, etc. |
||
| 201 | */ |
||
| 202 | public function getDatabaseEncoding() |
||
| 206 | |||
| 207 | /** |
||
| 208 | * Creates a database. |
||
| 209 | * |
||
| 210 | * @param string $database The name of the database to create |
||
| 211 | * @param string $encoding Encoding of the database |
||
| 212 | * @param string $tablespace (optional) The tablespace name |
||
| 213 | * @param string $comment |
||
| 214 | * @param string $template |
||
| 215 | * @param string $lc_collate |
||
| 216 | * @param string $lc_ctype |
||
| 217 | * |
||
| 218 | * @return int 0 success |
||
| 219 | */ |
||
| 220 | public function createDatabase( |
||
| 268 | |||
| 269 | /** |
||
| 270 | * Drops a database. |
||
| 271 | * |
||
| 272 | * @param string $database The name of the database to drop |
||
| 273 | * |
||
| 274 | * @return int 0 if operation was successful |
||
| 275 | */ |
||
| 276 | public function dropDatabase($database) |
||
| 283 | |||
| 284 | /** |
||
| 285 | * Alters a database |
||
| 286 | * the multiple return vals are for postgres 8+ which support more functionality in alter database. |
||
| 287 | * |
||
| 288 | * @param string $dbName The name of the database |
||
| 289 | * @param string $newName new name for the database |
||
| 290 | * @param string $newOwner The new owner for the database |
||
| 291 | * @param string $comment |
||
| 292 | * |
||
| 293 | * @return bool|int 0 success |
||
| 294 | */ |
||
| 295 | public function alterDatabase($dbName, $newName, $newOwner = '', $comment = '') |
||
| 333 | |||
| 334 | /** |
||
| 335 | * Renames a database, note that this operation cannot be |
||
| 336 | * performed on a database that is currently being connected to. |
||
| 337 | * |
||
| 338 | * @param string $oldName name of database to rename |
||
| 339 | * @param string $newName new name of database |
||
| 340 | * |
||
| 341 | * @return int 0 on success |
||
| 342 | */ |
||
| 343 | public function alterDatabaseRename($oldName, $newName) |
||
| 356 | |||
| 357 | /** |
||
| 358 | * Changes ownership of a database |
||
| 359 | * This can only be done by a superuser or the owner of the database. |
||
| 360 | * |
||
| 361 | * @param string $dbName database to change ownership of |
||
| 362 | * @param string $newOwner user that will own the database |
||
| 363 | * |
||
| 364 | * @return int 0 on success |
||
| 365 | */ |
||
| 366 | public function alterDatabaseOwner($dbName, $newOwner) |
||
| 375 | |||
| 376 | /** |
||
| 377 | * Returns prepared transactions information. |
||
| 378 | * |
||
| 379 | * @param null|string $database (optional) Find only prepared transactions executed in a specific database |
||
| 380 | * |
||
| 381 | * @return \PHPPgAdmin\ADORecordSet A recordset |
||
| 382 | */ |
||
| 383 | View Code Duplication | public function getPreparedXacts($database = null) |
|
| 395 | |||
| 396 | /** |
||
| 397 | * Returns all available process information. |
||
| 398 | * |
||
| 399 | * @param null|string $database (optional) Find only connections to specified database |
||
| 400 | * |
||
| 401 | * @return \PHPPgAdmin\ADORecordSet A recordset |
||
| 402 | */ |
||
| 403 | View Code Duplication | public function getProcesses($database = null) |
|
| 421 | |||
| 422 | // interfaces Statistics collector functions |
||
| 423 | |||
| 424 | /** |
||
| 425 | * Returns table locks information in the current database. |
||
| 426 | * |
||
| 427 | * @return \PHPPgAdmin\ADORecordSet A recordset |
||
| 428 | */ |
||
| 429 | View Code Duplication | public function getLocks() |
|
| 455 | |||
| 456 | /** |
||
| 457 | * Sends a cancel or kill command to a process. |
||
| 458 | * |
||
| 459 | * @param int $pid The ID of the backend process |
||
| 460 | * @param string $signal 'CANCEL' or 'KILL' |
||
| 461 | * |
||
| 462 | * @return int 0 success |
||
| 463 | */ |
||
| 464 | public function sendSignal($pid, $signal) |
||
| 490 | |||
| 491 | /** |
||
| 492 | * Vacuums a database. |
||
| 493 | * |
||
| 494 | * @param string $table The table to vacuum |
||
| 495 | * @param bool $analyze If true, also does analyze |
||
| 496 | * @param bool $full If true, selects "full" vacuum |
||
| 497 | * @param bool $freeze If true, selects aggressive "freezing" of tuples |
||
| 498 | * |
||
| 499 | * @return bool 0 if successful |
||
| 500 | */ |
||
| 501 | public function vacuumDB($table = '', $analyze = false, $full = false, $freeze = false) |
||
| 525 | |||
| 526 | /** |
||
| 527 | * Returns all autovacuum global configuration. |
||
| 528 | * |
||
| 529 | * @return array associative array array( param => value, ...) |
||
| 530 | */ |
||
| 531 | public function getAutovacuum() |
||
| 557 | |||
| 558 | /** |
||
| 559 | * Returns all available variable information. |
||
| 560 | * |
||
| 561 | * @return \PHPPgAdmin\ADORecordSet A recordset |
||
| 562 | */ |
||
| 563 | public function getVariables() |
||
| 569 | |||
| 570 | abstract public function fieldClean(&$str); |
||
| 571 | |||
| 572 | abstract public function beginTransaction(); |
||
| 573 | |||
| 574 | abstract public function rollbackTransaction(); |
||
| 575 | |||
| 576 | abstract public function endTransaction(); |
||
| 577 | |||
| 578 | abstract public function execute($sql); |
||
| 579 | |||
| 580 | abstract public function setComment($obj_type, $obj_name, $table, $comment, $basetype = null); |
||
| 581 | |||
| 582 | abstract public function selectSet($sql); |
||
| 583 | |||
| 584 | abstract public function clean(&$str); |
||
| 585 | |||
| 586 | abstract public function phpBool($parameter); |
||
| 587 | |||
| 588 | abstract public function hasCreateTableLikeWithConstraints(); |
||
| 589 | |||
| 590 | abstract public function hasCreateTableLikeWithIndexes(); |
||
| 591 | |||
| 592 | abstract public function hasTablespaces(); |
||
| 593 | |||
| 594 | abstract public function delete($table, $conditions, $schema = ''); |
||
| 595 | |||
| 596 | abstract public function fieldArrayClean(&$arr); |
||
| 597 | |||
| 598 | abstract public function hasCreateFieldWithConstraints(); |
||
| 599 | |||
| 600 | abstract public function getAttributeNames($table, $atts); |
||
| 601 | |||
| 602 | abstract public function hasSharedComments(); |
||
| 603 | |||
| 604 | abstract public function selectField($sql, $field); |
||
| 605 | } |
||
| 606 |
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: