Complete MP4

Assignments/MP4_CalebFontenot/src/mp4_calebfontenot/MP4_CalebFontenot.java

@@ -5,6 +5,8 @@
  */
 package mp4_calebfontenot;
 
+import java.util.Scanner;
+
 /**
  *
  * @author caleb
@@ -19,8 +21,7 @@ public class MP4_CalebFontenot {
      * @param CreditCard
      * @return
      */
-    public static boolean isValid(String CreditCard)
+    public static boolean isValid(String CreditCard) {
-    {
         int sumResult = MP4_CalebFontenot.sum(MP4_CalebFontenot.doubleDigitsAndSumSingleDigits(CreditCard), MP4_CalebFontenot.addOddNumbersFromRightToLeft(CreditCard));
         int divisionResult = sumResult % 10;
         if (debug) {
@@ -40,8 +41,7 @@ public class MP4_CalebFontenot {
      * @param step3 result form step 3
      * @return
      */
-    public static int sum(int step1andStep2, int step3)
+    public static int sum(int step1andStep2, int step3) {
-    {
         return step1andStep2 + step3;
     }
 
@@ -51,8 +51,7 @@ public class MP4_CalebFontenot {
      * @param -creditCard the credit card number to be processed.
      * @return the sum of digits at odd position from right to left.
      */
-    public static int addOddNumbersFromRightToLeft(String creditCard)
+    public static int addOddNumbersFromRightToLeft(String creditCard) {
-    {
         if (debug) {
             System.out.println("Now executing addOddNumbersFromRightToLeft()");
         }
@@ -61,7 +60,7 @@ public class MP4_CalebFontenot {
         int currentDigit, digitProduct, tensDigit, onesDigit, sum = 0;
         //System.out.println(creditCard.length());
 
-        for (int i = 0; i <= (creditCardLength - 1); i++) {
+        for (int i = (creditCardLength - 1); i >= 0; i--) {
             currentDigit = Character.getNumericValue(creditCard.charAt(i)); // Parses current digit as an integer so we can do math on it
             if (currentDigit % 2 != 0) { // Is this number an odd number?
                 sum += currentDigit;
@@ -81,8 +80,7 @@ public class MP4_CalebFontenot {
      * @param -creditCard the credit card number to be processed.
      * @return
      */
-    public static int doubleDigitsAndSumSingleDigits(String creditCard)
+    public static int doubleDigitsAndSumSingleDigits(String creditCard) {
-    {
         if (debug) {
             System.out.println("Now executing doubleDigitsAndSumSingleDigits()");
         }
@@ -91,12 +89,12 @@ public class MP4_CalebFontenot {
         int currentDigit, digitProduct, tensDigit, onesDigit, sum = 0;
         //System.out.println(creditCard.length());
 
-        for (int i = 0; i <= (creditCardLength - 1); i++){
+        for (int i = (creditCardLength - 1); i >= 0; i--) {
+            if (i % 2 == 0) {
                 currentDigit = Character.getNumericValue(creditCard.charAt(i)); // Parses current digit as an integer so we can do math on it
                 if (debug) {
                     System.out.println("current digit: " + currentDigit);
                 }
-            if (currentDigit % 2 == 0) { //Is this number an even number?
                 digitProduct = currentDigit * 2;
                 if (digitProduct > 9) { // Product is larger than 9. Typecast the integer back into a string so we can seperate the digits and add them together.
                     String workingString = Integer.toString(digitProduct);
@@ -109,12 +107,12 @@ public class MP4_CalebFontenot {
                     digitProduct = (tensDigit + onesDigit);
                 }
                 sum += digitProduct;
+            }
 
         }
         if (debug) {
             System.out.println("The sum is: " + sum);
         }
-        }
         return sum;
     }
 
@@ -123,21 +121,42 @@ public class MP4_CalebFontenot {
      *
      * @return a string with credit card number or 0.
      */
-    public static String menu()
+    public static String menu() {
+        String userInput = "";
+        Scanner input = new Scanner(System.in);
+        
+        while (!userInput.equals("0"))//user has not entered Q/q
         {
-        return "creditcard number or 0";
+            System.out.println("Press Q/q to quit");
+            System.out.println("Press C/c to enter a credit card");
+            userInput = input.next();
+            if (userInput.equalsIgnoreCase("q")) {
+                userInput = "0";
+            }
+            if (userInput.equalsIgnoreCase("c")) {
+                System.out.print("Please enter a credit card number: ");
+                userInput = input.next();
+                break;
+            }
+        }
+        
+        return userInput;
     }
 
     /**
      *
      * @param args
      */
-    public static void main(String[] args)
+    public static void main(String[] args) {
-    {
+
-        // DEBUG
-        //System.out.println(isValid("4388576018402626"));
         String sampleCreditCard = "4388576018410707";
-        boolean creditCardValidity = MP4_CalebFontenot.isValid(sampleCreditCard);
+        String userInput = menu();
+        if (userInput == "0") { // Stop program execution if credit card not entered
+            System.out.println("Credit card not entered!");
+            System.exit(0);
+        } 
+        
+        boolean creditCardValidity = MP4_CalebFontenot.isValid(userInput);
         String validityString;
         if (creditCardValidity) {
             validityString = "valid";
@@ -145,19 +164,7 @@ public class MP4_CalebFontenot {
             validityString = "invalid";
         }
 
-        System.out.println("The credit card " + sampleCreditCard + " is " + validityString);
+        System.out.println("The credit card " + userInput + " is " + validityString);
-
-        /*
-        String userInput = menu();
-        
-        while (!userInput.equals("0") )//user has not entered Q/q
-          {
-            MP4_CalebFontenot.doubleDigitsAndSumSingleDigits(userInput);
-            //complete the code
-            userInput = menu();
-            
-          }
-         */
     }
 
 }