How to check whether a given number is ArmStrong number or not?

package pack1;

public interface ArmStrongNumberIntf {

	/* Define the functional interface with SAM 'RdInput' */
	public Boolean RdInput(Integer intVal);

	/* Define the static method 'displayMsg' */
	static void displayMsg(Integer inpVal, boolean isArmStrong) {

		String res = isArmStrong ? "" : "Not ";
		System.out.println("The number " + inpVal + " is " + res + "ArmStrong Number");

		System.out.println();
	}
}

package pack1;

import java.util.ArrayList;
import java.util.Optional;
import java.util.logging.Logger;

class InputTheNumber {

	private int inputIntvalue;

	/* Declare the logger object for the class to display the log messages */
	static Logger logger = Logger.getLogger(InputTheNumber.class.getName());

	public boolean validateInputs(Integer inputAnInteger) {

		/* Fetch the class object's name from which this method is called */
		String cName = Thread.currentThread().getStackTrace()[2].getClassName();
		String mName = "validateInputs()";
		logger.info("This method '" + mName + "' called from the Class '" + cName + "'");

		/* Validating the function parameters using Optional Integer Array data type */
		Optional<Integer> inputVal = Optional.ofNullable(inputAnInteger);

		/*
		 * Fetch the value of the Optional Integer inputAnInteger using 'isPresent'
		 * condition check. If the value is available use 'get' method otherwise simply
		 * return 'false' to stop the program execution without proceeding further.
		 */
		if (inputVal.isPresent()) {
			setInputIntvalue(inputVal.get());
			System.out.println("The given number is " + getInputIntvalue());
		} else
			return false;

		logger.info("The provided Input validated Successfully");
		return true;
	}

	/* Define getter and setters for an inputIntvalue int variable */
	public int getInputIntvalue() {
		return inputIntvalue;
	}

	public void setInputIntvalue(int inputIntvalue) {
		this.inputIntvalue = inputIntvalue;
	}
}

class ArmStrongNumber_Using_String extends InputTheNumber implements ArmStrongNumberIntf {

	public Boolean RdInput(Integer inpVal) {

		/* Fetch the class object's name from which this method is called */
		String cName = Thread.currentThread().getStackTrace()[2].getClassName();
		String mName = "RdInput";
		logger.info("This method '" + mName + "' called from the Class '" + cName + "'");

		/* Initialize the sumCheck value to 0, and initialize isArmStrong to false */
		int sumCheck = 0;
		boolean isArmStrong = false;

		if (validateInputs(inpVal)) {

			String numToStr = String.valueOf(getInputIntvalue());
			int numLen = numToStr.length();

			// Calculate the sum of each digit's cube power value from any side
			for (; numLen > 0; numLen--)
				if (Character.isDigit(numToStr.charAt(numLen - 1)))
					sumCheck = (int) (sumCheck + Math.pow(Character.getNumericValue(numToStr.charAt(numLen - 1)), 3));

			// Compare the sumCheck with actual number
			if (sumCheck == inpVal)
				isArmStrong = true;
		} else
			logger.info("The given Input number is null");

		ArmStrongNumberIntf.displayMsg(inpVal, isArmStrong);
		return isArmStrong;
	}
}

class ArmStrongNumber_Using_CoreLogic extends InputTheNumber implements ArmStrongNumberIntf {

	public Boolean RdInput(Integer inpVal) {

		/* Fetch the class object's name from which this method is called */
		String cName = Thread.currentThread().getStackTrace()[2].getClassName();
		String mName = "RdInput";
		logger.info("This method '" + mName + "' called from the Class '" + cName + "'");

		/* Initialize the sumCheck value to 0, and initialize isArmStrong to false */
		int sumCheck = 0, remValue;
		boolean isArmStrong = false;

		if (validateInputs(inpVal)) {

			int storeNum = getInputIntvalue();
			while (storeNum != 0) {
				remValue = storeNum % 10;
				sumCheck = sumCheck + (remValue * remValue * remValue);
				storeNum = storeNum / 10;
			}
			// Compare the sumCheck with actual number
			if (sumCheck == inpVal)
				isArmStrong = true;
		} else
			logger.info("The given Input number is null");

		ArmStrongNumberIntf.displayMsg(inpVal, isArmStrong);
		return isArmStrong;
	}
}

class ArmStrongNumber_Using_Stream extends InputTheNumber implements ArmStrongNumberIntf {

	public Boolean RdInput(Integer inpVal) {

		/* Fetch the class object's name from which this method is called */
		String cName = Thread.currentThread().getStackTrace()[2].getClassName();
		String mName = "RdInput";
		logger.info("This method '" + mName + "' called from the Class '" + cName + "'");

		/* Initialize the flag isArmStrong to false */
		boolean isArmStrong = false;

		if (validateInputs(inpVal)) {

			String strVal = String.valueOf(getInputIntvalue());

			ArrayList<Integer> arrOfDigits = new ArrayList<Integer>();
			for (char ch : strVal.toCharArray())
				arrOfDigits.add(Character.getNumericValue(ch));

			// Applying map and reduce method to find our sum of cubes
			int sumOfCubes = arrOfDigits.stream().map(a -> a * a * a).reduce(0, (x, y) -> x + y);
			if (sumOfCubes == inpVal)
				isArmStrong = true;
		} else
			logger.info("The given Input number is null");

		ArmStrongNumberIntf.displayMsg(inpVal, isArmStrong);
		return isArmStrong;
	}
}

public class ArmstrongNumberJ8 {

	public static void main(String args[]) {

		/*
		 * create the class object ArmStrongNumber_Using_String, and call the method
		 * RdInput
		 */

		ArmStrongNumber_Using_String ANUS = new ArmStrongNumber_Using_String();
		ANUS.RdInput(154);
		ANUS.RdInput(null);

		/*
		 * create the class object ArmStrongNumber_Using_CoreLogic, and call the method
		 * RdInput
		 */

		ArmStrongNumber_Using_CoreLogic ANUCL = new ArmStrongNumber_Using_CoreLogic();
		ANUCL.RdInput(407);
		ANUCL.RdInput(null);

		/*
		 * create the class object ArmStrongNumber_Using_Stream, and call the method
		 * RdInput
		 */

		ArmStrongNumber_Using_Stream ANUStream = new ArmStrongNumber_Using_Stream();
		ANUStream.RdInput(371);
		ANUStream.RdInput(null);
	}
}