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I had started programming in Java 2 years back. Seniors in our project at that time had advised me to append 'obj' to the name of the object which is being created.

Ex:

Car objCar = new Car("Ferrari");

Here objCar is what I am talking about. But many at Stack Overflow had opposed to it and now I find that this shouldn't be the way naming of an object should be done. I am clear with naming conventions when collections are used but I am confused when objects of general classes are created.

Can anyone shed some light on it?

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    Everything in Java except primitive types are objects. Would you prepend obj on every variable name? Commented Apr 27, 2012 at 5:45
  • this obj... stuff if from old times. Commented Apr 27, 2012 at 5:45
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    if for you it is more simple to identify your attribute... why not with "obj" Commented Apr 27, 2012 at 5:46
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    see this iwombat.com/standards/JavaStyleGuide.html Commented Apr 27, 2012 at 5:48
  • 4
    Objects don't have names. Variables have names. Commented Apr 27, 2012 at 7:35

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Just call it car. Hungarian notation is not used by Sun/Oracle.

Name your variables in a manner which describes their use. But you don't need to indicate the type in the variable name. You already specified the type in the variable declaration. IDEs will show you the type of the variable if you mouse-over them so that information is always readily available.

You should use lowercaseStartingCamelCase for variable names and method names, and UppercaseStartingCamelCase for class names.

If you want to read how Sun/Oracle do things, you can read their Code Conventions for the Java Programming Language.

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5 Comments

What is the standards followed in naming the objects ? Just the class name with small cased letter in the beginning?
@Ajj Consider naming it something meaningful, like what it does/is used for. That's the "standard". If you mean grammatical standards, variable names start with a lowercase letter and use camelCase.
Am fine with accessors and mutator methods naming. I am just confused with general classes like 'Car', 'Student', 'Machine', etc..
Name it after what it's actually being used for, not after the class name. There's no general rule for that.
Thanks for the link Greg. Had browsed it before but dint help me clarifying my doubt. Anyways, now I understood hungarian way of naming should be completely omitted.
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Your example is a bit too trivial. In reality you would never name a field of object type "Car" as "car". Likewise you never name an "Integer" type as "integer".

Instead, the use names that tell the reader what the field is used for. Some examples:

private Transport preferredTransportMethod; private int invoiceCounter;

Prefixing field type is not used commonly is Java. However, class member are sometimes prefixed with lower case "m" to prevent accidental self assignments in setter methods.

private long mTripDurationMillis;
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Name your objects what they are, it makes reading and refactoring easier.

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naming conventions for objects in java are just names. For example 

Car car = new Car("Ferrari");

The remnants of Hungarian notation have been abandoned mainly because of the added support the IDE's have provided for navigation.

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class name in small letters is Sun/Oracle standard.

when you are working for a company,

depending upon project naming conventions it may vary.

Car car=new Car(); //good to follow

if It is Singleton pattern,you may give a name like below

 private static final Car singletonCar=new Car();
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4 Comments

Singletons should not be identified in the field name. The fact that they are singletons should only be visible when the field is initialized. If something else is needed, then it is a signal about something being done wrong. In your example, the wrong thing is that you allow more than one instance of your Car-singleton.
edited.there are many ways to create a singleton it is one of them.This kind of naming convention is maintained just for readability .
The idea of singleton is that you can only initialize one instance of the object. A final field does not prevent you from creating two Car objects. You have to build the restriction into the Car object itself. Initializing singletons is pretty well documented. Please Google it. Once you have acquired a reference to a singleton, there should not be any need to label it as a singleton in the field name. The singleton should be implemented in such a robust manner that the user does not have to know about it after initialization. It should act just like any other object shared by many threads.
just I am again saying there are n number of ways to create a singleton this is one ,of course traditional way,you just go through wikipedia link,discusion about singleton is offtrack here. and moreover when I am giving singletonCar ,it is for all team members,when you are working in a team all team members may not be of same level knowledge and we can not assume that .That is for readability and maintainablity of code.
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If you use more objects, I do it like this:

Car carFerrari = new Car("Ferrari"); Car carFord = new Car("Ford"); Car carAudi = new Car("Audi");

Of course, the names can be "ferrari", "ford" and "audi", but I like to refer to objects of same type.

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Being you are senior , after all I can suggest you some naming convention related to your doubts. As we know all class name are started with first capital letter, suppose class "MyTest" when object we need to create of this class it should be "mytest". Object name should be in this format. According to the jakarta project menifesto I found this type of convection and the are following . Other than jakarta, Sun API including IDE for development also they are using this. Hope ,it will help you.Yes I am new.Thanks for your helpful information.

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Manoj, it seems you are new to SO. Dear etc., are not supported terms in SO and answer don't need to be code formatted.

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