Java Identifiers

Java Identifiers

All Java components require names. Names used for classes, variables, and methods are called identifiers.

In Java, there are several points to remember about identifiers. They are as follows −

• All identifiers should begin with a letter (A to Z or a to z), currency character {$ (Dollar Symbol)} or an underscore (_).
• All identifiers can not start with spaces and can not contain spaces.
• After the first character, identifiers can have any combination of characters.
  
• A key word cannot be used as an identifier.
  
• Most importantly, identifiers are case sensitive.
  
• Area, area, ARea, AREA are four different identifiers.
• Examples of legal identifiers: age, $salary, _value, __1_value.
• Examples of illegal identifiers: 123abc, -salary.