Java 'final' Keyword Tutorial
The final keyword in Java is used to restrict the user. The java final keyword can be used in many contexts.
Final can be: variable, method, and class.
1. Java Final Variable
If you make any variable as final, you cannot change the value of final variable (It will be constant).
class Bike9 {
final int speedlimit = 90; //final variable
void run() {
speedlimit = 400; //Compile Time Error
}
}2. Java Final Method
If you make any method as final, you cannot override it.
class Bike {
final void run() { System.out.println("running"); }
}
class Honda extends Bike {
void run() { System.out.println("running safely with 100kmph"); } //Compile Time Error
}3. Java Final Class
If you make any class as final, you cannot extend it.
final class Bike {}
class Honda1 extends Bike { //Compile Time Error
void run() { System.out.println("running safely with 100kmph"); }
}