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I am reading the book Clean Code http://www.amazon.com/Clean-Code-Handbook-Software-Craftsmanship/dp/0132350882

The author mentions that you should avoid words like Manager, Processor, Data or Info in the name of the class. I have used these everywhere. What are some better names? I have a class that is responsible for starting and stopping connections. So I named it ConnectionManager.

Cody Gray - on strike
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uriDium
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  • Does it give a specific reason for this? – Wade Tandy Apr 06 '11 at 16:16
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    I think the reason to avoid "Manager" is that it doesn't say anything specific. If there was an universal replacement, the replacement would be just as bad for exactly the same reasons. – Pascal Cuoq Apr 06 '11 at 16:19
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    possible duplicate of [Naming Classes - How to avoid calling everything a "Manager"?](http://stackoverflow.com/questions/1866794/naming-classes-how-to-avoid-calling-everything-a-whatevermanager) – David Hall Apr 06 '11 at 16:27
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    Off the top of my head, would your ConnectionManager be better as a ConnectionFactory or just Connector? Even if connections can't stop themselves (for instance with a `close()` method), it's not a total outrage for creation and destruction to be linked, so you're not really hiding anything if you highlight that creating connections is the main thing you do (hence use that as the name), and stopping them is the natural consequence... – Steve Jessop Apr 06 '11 at 16:35
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    ... The trouble with Manager is that it doesn't tell us that your class starts or stops connections, or what else (if anything) it does with them. For all we know from the name it just bosses them around a bit and takes the credit for everything they achieve. – Steve Jessop Apr 06 '11 at 16:36
  • Some more of my favorites along these lines - Helper, Common, Core, Utilities – Arnis Lapsa Apr 06 '11 at 16:37

8 Answers8

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Wait!

The point of the book is, that Manager in the classname means the class does more than one thing. Robert C. Martin refers in this section to the Single Responsibility Principle!

This is not about the name, its about the classes which are usually named like this. Changing the name won't reduce the responsibilities of a class!

myAces
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    Single Responsibility Principle doesn't mean that class should do just one thing. Actually first thing the author says in chapter 7: SRP of his book Clean Architecture is that SRP doesn't mean that class should do just one thing. SRP means that "A module should have one, and only one, reason to change". – xstmpx Sep 30 '20 at 13:48
  • Doesn't doing more than one thing be more reasons to change the module, a little confused here. Although I do think that there is essentially no need for a Book Manager and call it rather a "BookLibrary". – Chaks Apr 13 '22 at 05:19
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My guess is the book makes this point because it's trying to encourage you to choose a more descriptive name for your class. There's no "naming convention" to follow here; that's the problem you fell into in the first place. Any universal naming convention won't be able to consider the specific class and choose the best name for it. Expressivity is more important than following a naming convention. Calling a class a "Manager" or a "Processor" doesn't say very much about it and what it does to a person who is reading your code for the first time.

If you really can't think of anything better, there's nothing inherently wrong with naming a class ConnectionManager. But I'd at least name it after the type of collections that it manages. Or maybe how it manages those collections. Or why it manages those collections.

Also consider that following "one-size-fits-all" rules rarely helped anyone to write better code (at least, not better in the sense of "more understandable" or "more expressive). I tend to postfix the names of all my native wrapper classes with Manager. For example, I might have classes called DwmManager, or VisualStylesManager. In that very specific case, it does mean something to me. If I see a class named Manager in my code base, I know it wraps a bunch of closely-related functionality. You have to make the decision on a case-by-case basis, understanding what you're ultimately trying to accomplish.

If you read Code Complete and missed the part about writing code that's clear and understandable (and therefore maintainable), you might have missed the point.

Cody Gray - on strike
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In the example of your ConnectionManager class, it is possible that the class is more indicative of a design flaw which necessitates a "bad" name. Is the class doing something besides performing actions that could just as easily be done in a singleton subclass called MyDatabaseConnection?

Wade Tandy
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  • I used the word connection but it is to another machine not a database. The ConnectionManager starts and stops those connections. – uriDium Apr 06 '11 at 17:44
  • I'm saying is it might be better to get rid of ConnectionManager and instead subclass Connection as something like ComputerConnection. This class can handle its own lifecycle, so you won't need a cumbersome Manager class. – Wade Tandy Apr 06 '11 at 21:02
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Take for instance name DataProcessor.

First it is true that each function works with data, takes data or return some data unless is 

void f(void)

But if it is such type of function it absolutely makes something so it is Processor in any case.

DataProcessor is basically anything because it does no say what it manipulates and how. So you should replace

DataProcessor with UserInfoStore for instance.

Flot2011
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Luka Rahne
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OH, NO !!

Please don't be intimidated by general pronouncements about how you "should" name things. They are your things, after all. Maybe your name "Manager" is better than "Connection Manager" because it's shorter. Especially so if that section of your code mainly manages "connections" and little else.

I believe that such books have very useful ideas, but only for coders who will never read them. Why? Because engineers who do read such books have already internalized and incorporated the soundest of the principles in them. And coders who won't read them don't care.

Pete Wilson
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"Helper", "Common", "Core", "Utilities" seems equal or worst than "Manager". Them don't say nothing about what they do.
"Factory" is absolutely wrong here.
Alternative names are "Coordinator" or "Controller".

yous said: I have a class that is responsible for starting and stopping connections. So I named it ConnectionManager.

If the class just "start" and "stop" the connection, why not "ConnectionSwitcher" ?

you said: I have used these everywhere.

I have many *Manager classes too. Today I decided to change the name of "AccountManager". It uses the Account repository to perform CRUD operations.

I splitted it in "AccountSecurity" and "AccountOperations".

Them exists in MyProject.BusinessLogic namespace and both uses AccountRepository class that expose the CRUD methods. The former is responsible for actions like "Login" and "ChangePassword". The latter is responsible for CRUD operations against the database but regulated by some logic, for example if exists some registry records for the Account it cannot be deleted. (The "AccountOperations" uses also other repositories to retrieve needed informations)

I'm not happy with "operations" and I'm searching something better (Coordinator, Supervisor...) but it is a start.

My case would be an example of the way to think at it.

Alex 75
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    Probably I'll return to use "*Manager" at least for the CRUD (extended) operations, because they really "manage" the specific item. For specific actions like search and grouping for analisys I already started to create *Analisys and *Provider classes. – Alex 75 Oct 29 '16 at 13:36
  • This could help someone : I have started to think on naming it Operators. Like `AccountOperator` which essentially is responsible to _operate_ on certain things. This is not as vague as `Manager` and not very concrete also. `Manager` classes can _have_ operator classes to rely for operations OR a `Mediator` class to delegate some of its lower level implementation responsibilities, depending upon the situation and size of the problem – krozaine Feb 25 '22 at 09:57
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I tend to use the word "Initialize" or "Initializer" quite frequently. If it's anything else, I usually think of a synonym that is really long compared to the first thing I thought of. I also use the term "Parser" and other things.

Freesnöw
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dont be too concerned about the name, dont pay much attention to it unless you or someone really dont like it.

James.Xu
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    Naming is one of the most important things in software development – Arnis Lapsa Apr 06 '11 at 16:35
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    @Arnis: I feel like that statement goes a bit too far in the *other* direction. Although I agree that naming (insofar as it helps you to write clear, understandable code) is important and not to be underestimated. – Cody Gray - on strike Apr 06 '11 at 16:39
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    @Cody it surely is. Without naming, You are absolutely unable to create natural abstractions. Without abstractions You end up with procedural code (think 20k lines in a "class"). – Arnis Lapsa Apr 06 '11 at 16:40