Constants (final keyword)
When you do not want a variable's value to change, use the final keyword.
A variable declared with final becomes a constant, which means unchangeable and read-only:
Example
final int myNum = 15;
myNum = 20; // Error: cannot assign a value to final variable 'myNum'
When to Use final?
You should declare variables as final when their values should never change. For example, the number of minutes in an hour, or your birth year:
Example
final int MINUTES_PER_HOUR = 60;
final int BIRTHYEAR = 1980;
Note: By convention, final variables in Java are usually written in upper case (e.g.
BIRTHYEAR). It is not required, but useful for code readability and common for many programmers.
