Core Java Tutorial

                                                           Legal identifiers in java

All the java component like class, variable ,and methods need names,in java these names are called identifiers
so There is some rules for legal identifiers that are as follows
1.Identifiers must start with a letter,$,_
2.it can't start with number
3.there is no limit of size
4.we can't use java keyword
5.Identifier is case sensitive

examples

 some legal identifiers---
int  _a;
int $$;
int ____________a;
int this_is_identifiers;

some illegal identifiers
int :b;
int -d;
int 55;
int e#;
int .f;
int  !ee;


Refrences
Kathey sierra & Bert Bates