Java Identifiers

---

• Identifiers are programmer defined tokens.

• They are used fro naming classes, methods, variables, packages, and interfaces in a program.

Rules for a Legal Identifier :

1. They can be a set of alphabet, digits, underscore ( _ ) and dollar ( $ ) character.

2. They must not begin with digit .

3. Since Java is case sensitive language, Uppercase and Lowercase letters are distinct.

4. They can be of any length.

5. They must not be a keyword.

---

Example of legal identifier :

     arena , s_count
     marks40
     class_one

---

Example of illegal identifier :

     1sst
     2nd number
     oh!god

advertisement