final variables
A final variable cannot be modified.
You must initialize a final variable when it is declared. A final variable is essentially a constant.
public class Main {
final int FILE_NEW = 1;
final int FILE_OPEN = 2;
}
Using final to Prevent Overriding
Methods declared as final cannot be overridden.
class Base {
final void meth() {
System.out.println("This is a final method.");
}
}
class B extends A {
void meth() { // ERROR! Can't override.
System.out.println("Illegal!");
}
}
If you try to compile the code above, the following error will be generated by the compiler.
D:\>javac Main.java
Main.java:7: cannot find symbol
symbol: class A
class B extends A {
^
1 error