Check if a Credit Card is Valid

Validate.java

//*******************************************************************
//Assignment: Assignment 4
//Account: TAM154
//
//Author: Tori Murray
//
//
//Honor Code: I pledge that this program represents my own program code.
//
//*******************************************************************
package validate;

//Import a scanner
import java.util.Scanner;


/**
 *
 * @author a_nog
 */
public class Validate {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        //Add a scanner
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter a credit card number as a long integer: ");
        long input = sc.nextLong();

        if (isValid(input) == true) {
            System.out.println("\n" + input + " is Valid. ");
        } else {
            System.out.println("\n" + input + " is Invalid. ");
        }
    }
  /** Return true if the card number is valid */
    //if the number in step 4 is divisible by 10, it is valid
    //Sum of the results of step 2 and 3 divisible by 10=valid
    public static boolean isValid(long number) {
         int total = sumOfDoubleEvenPlace(number) + sumOfOddPlace(number);
         if ((total % 10 == 0) && (prefixMatched(number, 1) == true) && (getSize(number)>=13 ) && (getSize(number)<=16 )) {
            return true;
        } else {
            return false;
        }
    }
    
  /** Return this number if it is a single digit, otherwise, return the sum of the two digits */
    public static int getDigit(int number) {
        if (number <= 9) {
            return number;
        } else {
            int firstDigit = number % 10;
            int secondDigit = (int) (number / 10);
            return firstDigit + secondDigit;
        }
    }
      /** Get the result from Step 2 */   
    public static int sumOfDoubleEvenPlace(long number) {
        int result = 0;
        long temp = 0;
        while (number > 0) {
            temp = number % 100;
            result += getDigit((int) (temp / 10) * 2);
            number = number / 100;
        }
        return result;
    }
     /** Return sum of odd-place digits in number */ 
    public static int sumOfOddPlace(long number) {
        int result = 0;
        while (number > 0) {
            result += (int) (number % 10);
            number = number / 100;
        }
        return result;
    }
    /** Return true if the digit d is a prefix for number */
    public static boolean prefixMatched(long number, int d) {
            if ((getPrefix(number, d) == 4)|| (getPrefix(number, d) == 5)|| (getPrefix(number, d) == 3)) {
            if (getPrefix(number, d) == 3) {
                System.out.println("\nVisa Card ");
            } else if (getPrefix(number, d) == 5) {
                System.out.println("\nMaster Card ");
                System.out.println("\nAmerican Express Card ");
            }
            return true;
        } else {
            return false;
        }
    }

     /** Return the number of digits in d */ 
    public static int getSize(long d) {
        int count = 0;
        while (d > 0) {
            d = d / 10;
            count++;
        }
        return count;
    }

     /** Return the first k number of digits from number. If the number of digits in number is less than k, return number. */
    public static long getPrefix(long number, int k) {
        if (getSize(number) < k) {
            return number;
        } else {
            int size = (int) getSize(number);
            for (int i = 0; i < (size - k); i++) {
                number = number / 10;
            }
            return number;
        }
    }

       
    }