Tech By Bug

import java.util.regex.Pattern;

public class VerhoeffAlgorithm {
static int[][] d = new int[][]
 {
 {0, 1, 2, 3, 4, 5, 6, 7, 8, 9},
 {1, 2, 3, 4, 0, 6, 7, 8, 9, 5},
 {2, 3, 4, 0, 1, 7, 8, 9, 5, 6},
 {3, 4, 0, 1, 2, 8, 9, 5, 6, 7},
 {4, 0, 1, 2, 3, 9, 5, 6, 7, 8},
 {5, 9, 8, 7, 6, 0, 4, 3, 2, 1},
 {6, 5, 9, 8, 7, 1, 0, 4, 3, 2},
 {7, 6, 5, 9, 8, 2, 1, 0, 4, 3},
 {8, 7, 6, 5, 9, 3, 2, 1, 0, 4},
 {9, 8, 7, 6, 5, 4, 3, 2, 1, 0}
 };

static int[][] p = new int[][]
 {
 {0, 1, 2, 3, 4, 5, 6, 7, 8, 9},
 {1, 5, 7, 6, 2, 8, 3, 0, 9, 4},
 {5, 8, 0, 3, 7, 9, 6, 1, 4, 2},
 {8, 9, 1, 6, 0, 4, 3, 5, 2, 7},
 {9, 4, 5, 3, 1, 2, 6, 8, 7, 0},
 {4, 2, 8, 6, 5, 7, 3, 9, 0, 1},
 {2, 7, 9, 3, 8, 0, 6, 4, 1, 5},
 {7, 0, 4, 6, 9, 1, 3, 2, 5, 8}
 };

static int[] inv = {0, 4, 3, 2, 1, 5, 6, 7, 8, 9};

public static boolean validateVerhoeff(String num){
int c = 0;
int[] myArray = StringToReversedIntArray(num);
for (int i = 0; i < myArray.length; i++){
   c = d[c][p[(i % 8)][myArray[i]]];
 }
return (c == 0);
}

private static int[] StringToReversedIntArray(String num){
int[] myArray = new int[num.length()];
for(int i = 0; i < num.length(); i++){
   myArray[i] = Integer.parseInt(num.substring(i, i + 1));
 }
myArray = Reverse(myArray);
return myArray;
}

private static int[] Reverse(int[] myArray){
int[] reversed = new int[myArray.length];
for(int i = 0; i < myArray.length ; i++){
  reversed[i] = myArray[myArray.length - (i + 1)];
 }
 return reversed;
}

public static boolean validateAadharNumber(String aadharNumber){
 Pattern aadharPattern = Pattern.compile("\\d{12}");
 boolean isValidAadhar = aadharPattern.matcher(aadharNumber).matches();
 if(isValidAadhar){
 isValidAadhar = VerhoeffAlgorithm.validateVerhoeff(aadharNumber);
 }
 return isValidAadhar;
}
}

Now call validateAadharNumber and pass aadhar number to validate, It will return true if aadhar

number is valid else false.

public class ValidateAadharNo {
public static void main(String[] args) {
 String aadharNumber ="432323232112";
  if(Verhoef fAlgorithm.validateAadharNumber(aadharNumber)) {
    System.out.println("Given Aadhar Number is valid :"+aadharNumber);
  }else {
    System.out.println("Given Aadhar Number is not valid :"+aadharNumber);
  }
 }
}