Millistel juhtudel tuleks Java-s kasutada final-muutujat?

The final modifier in Java is used to restrict changes and enhance code security. It should be applied in the following cases:

• For variables: to make them constants, whose values cannot be changed after initialization.
• For methods: to prevent overriding the method in subclasses, which is important for maintaining logic and preventing errors.
• For classes: to prevent inheritance, which is useful when a class should remain unchanged and protected from extension.

Example:

final class Constants {
    public static final double PI = 3.14159;
}

class Base {
    public final void show() {
        System.out.println("Final method");
    }
}

class Derived extends Base {
    // Error: cannot override final method show()
}