Data class smell
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| − | The data class smell is present where a class has only fields, getters, setters and nothing else. | + | The data class smell is present where a class has only fields, getters, setters and nothing else. It lacks the behaviours that make it a proper, stand-alone class (and consequently, the instantiated object). |
| − | == Refactoring | + | == Validity == |
| + | |||
| + | What exactly is wrong with data classes? Data classes always seemed useful and necessary to me - for example, geometric constructs such as points and vectors (Have you tried types ? Are you using the right language ? (Let's move this to the discussion page, chaps --[[User:Lukas Korsika|Lukas Korsika]] 00:32, 21 October 2010 (UTC) )). Data classes can definitely be misused, but I don't think this smell should be considered an automatic refactoring job. | ||
| + | |||
| + | == Refactoring techniques == | ||
* [[Encapsulate Field]] - if there are public fields | * [[Encapsulate Field]] - if there are public fields | ||
| − | * [[Encapsulate Collection]] - if there is collections in the class. This is to ensure unmodifiable, read only collections | + | * [[Encapsulate Collection]] - if there is collections in the class. This is to ensure unmodifiable, read only collections is returned |
* [[Remove Setting Method]] - for fields whose values should not be changed | * [[Remove Setting Method]] - for fields whose values should not be changed | ||
| − | * [[Move Method]] or [[Extract Method]] - move method or extract method to move the behavior from the clients to data class | + | * [[Move Method]] or [[Extract Method]] - move method or extract method to move the behavior from the clients (that use the accessors of the data class) to data class |
== See also == | == See also == | ||
| − | * [[ | + | * [[Eliminate irrelevant classes]] |
* [[Keep related data and behavior in one place]] | * [[Keep related data and behavior in one place]] | ||
| + | * [[Code smells]] | ||
| + | * [[Refactoring]] | ||
| + | |||
| + | {{Template:CodeSmells}} | ||
| + | |||
| + | [[Category:Code smells]] | ||
Latest revision as of 03:07, 25 November 2010
The data class smell is present where a class has only fields, getters, setters and nothing else. It lacks the behaviours that make it a proper, stand-alone class (and consequently, the instantiated object).
Validity
What exactly is wrong with data classes? Data classes always seemed useful and necessary to me - for example, geometric constructs such as points and vectors (Have you tried types ? Are you using the right language ? (Let's move this to the discussion page, chaps --Lukas Korsika 00:32, 21 October 2010 (UTC) )). Data classes can definitely be misused, but I don't think this smell should be considered an automatic refactoring job.
Refactoring techniques
- Encapsulate Field - if there are public fields
- Encapsulate Collection - if there is collections in the class. This is to ensure unmodifiable, read only collections is returned
- Remove Setting Method - for fields whose values should not be changed
- Move Method or Extract Method - move method or extract method to move the behavior from the clients (that use the accessors of the data class) to data class
See also
