OOP Naming Conventions

When programming object-oriented programming (OOP) a standard naming scheme for classes, objects, variables, and methods is important. Here are two naming schemes I know of (I generally use the second one):

Naming Scheme 1:

a. Class name: concatenated words, each word should start with uppercase.

§ E.g:  Database, Person, BankAccount, MyLinkedList etc…

b. Objects, variables, methods: concatenated words, first word all lowercase, subsequent words should start with uppercase.

§ E.g (objects): $array = new Array(), $myAccount  = new Account();

§ E.g (variables): $i, $nodeList, $myCounter;

§ E.g (methods): deposit(), getName(), setName(), getAccountNumber();

Naming Scheme 2:

a. Class name: concatenated words, each word should start with uppercase.

§ E.g: Database, Person, BankAccount, MyLinkedList etc…

b. Methods: concatenated words, first word all lowercase, subsequent words should start with uppercase.

§ E.g: deposit(), getName(), setName(), connectDatabase();

c.       Objects, variables: all lowercase concatenated words separated by underscores.

d.      Constant variables: all uppercase concatenated words separated by underscores.

§ E.g: $PI = 3.14, $GRAVITY = 9.8, $ARRAY_SIZE = 50, etc…