Class ISINCheckDigit

java.lang.Object
org.apache.commons.validator.routines.checkdigit.ModulusCheckDigit
org.apache.commons.validator.routines.checkdigit.ISINCheckDigit
All Implemented Interfaces:
Serializable, CheckDigit

public final class ISINCheckDigit extends ModulusCheckDigit
Modulus 10 ISIN (International Securities Identifying Number) Check Digit calculation/validation.

ISIN Numbers are 12 character alphanumeric codes used to identify Securities.

Check digit calculation uses the Modulus 10 Double Add Double technique with every second digit being weighted by 2. Alphabetic characters are converted to numbers by their position in the alphabet starting with A being 10. Weighted numbers greater than ten are treated as two separate numbers.

See Wikipedia - ISIN for more details.

Since:
Validator 1.4
Version:
$Revision: 1713331 $
See Also:
  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      See Also:
    • ISIN_CHECK_DIGIT

      public static final CheckDigit ISIN_CHECK_DIGIT
      Singleton ISIN Check Digit instance
    • POSITION_WEIGHT

      private static final int[] POSITION_WEIGHT
      weighting given to digits depending on their right position
  • Constructor Details

    • ISINCheckDigit

      public ISINCheckDigit()
      Construct an ISIN Indetifier Check Digit routine.
  • Method Details

    • calculateModulus

      protected int calculateModulus(String code, boolean includesCheckDigit) throws CheckDigitException
      Calculate the modulus for an ISIN code.
      Overrides:
      calculateModulus in class ModulusCheckDigit
      Parameters:
      code - The code to calculate the modulus for.
      includesCheckDigit - Whether the code includes the Check Digit or not.
      Returns:
      The modulus value
      Throws:
      CheckDigitException - if an error occurs calculating the modulus for the specified code
    • weightedValue

      protected int weightedValue(int charValue, int leftPos, int rightPos)

      Calculates the weighted value of a charcter in the code at a specified position.

      For Luhn (from right to left) odd digits are weighted with a factor of one and even digits with a factor of two. Weighted values > 9, have 9 subtracted

      Specified by:
      weightedValue in class ModulusCheckDigit
      Parameters:
      charValue - The numeric value of the character.
      leftPos - The position of the character in the code, counting from left to right
      rightPos - The positionof the character in the code, counting from right to left
      Returns:
      The weighted value of the character.