Modifier isFinal(mod) method in Java with Examples

The isFinal(mod) method of java.lang.reflect.Modifier is used to check if the integer argument includes the final modifier or not. If this integer parameter represents final type Modifier then method returns true else false.

Syntax:

public static boolean isFinal(int mod)

Parameters: This method accepts a integer names as mod represents a set of modifiers.

Return: This method returns true if mod includes the final modifier; false otherwise.

Below programs illustrate isFinal() method:
Program 1:

// Java program to illustrate isFinal() method

import java.lang.reflect.*;

public class GFG {

    public static void main(String[] args)
    {

        // get Method class object
        Method[] methods
            = Shape.class.getMethods();

        // get Modifier Integer value
        int mod = methods[0].getModifiers();

        // check Modifier is final or not
        boolean result = Modifier.isFinal(mod);

        System.out.println("Mod integer value "
                           + mod + " is final : "
                           + result);
    }

    class Shape {

        public final void drawShape() {}
    }
}

Output:

Mod integer value 17 is final : true

Program 2:

// Java program to illustrate isFinal()

import java.lang.reflect.*;

public class GFG {

    public static void main(String[] args)
    {

        // get Method class object
        Method[] methods
            = Numbers.class.getMethods();

        // get Modifier Integer value
        int mod1 = methods[0].getModifiers();
        int mod2 = methods[1].getModifiers();

        // check Modifiers are final or not
        boolean result1 = Modifier.isFinal(mod1);
        boolean result2 = Modifier.isFinal(mod2);

        // print results
        System.out.println("Mod integer value "
                           + mod1 + " for method "
                           + methods[0].getName()
                           + " is final : "
                           + result1);

        System.out.println("Mod integer value "
                           + mod2 + " for method"
                           + methods[1].getName()
                           + " is final : "
                           + result2);
    }

    // sample final class
    abstract class Numbers {

        public abstract int initializeNumber();
        public final int declareNumbers()
        {
            return 0;
        }
    }
}

Output:

Mod integer value 1025 for method initializeNumber is final : false
Mod integer value 17 for methoddeclareNumbers is final : true

References: https://docs.oracle.com/javase/10/docs/api/java/lang/reflect/Modifier.html#isFinal(int)