org.apache.commons.validator.routines.checkdigit

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:

$Revision$

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static CheckDigit	ISIN_CHECK_DIGIT Singleton ISIN Check Digit instance

Constructor Summary

Constructors

Constructor and Description
ISINCheckDigit() Construct an ISIN Indetifier Check Digit routine.

Method Summary

Modifier and Type	Method and Description
protected int	calculateModulus(String code, boolean includesCheckDigit) Calculate the modulus for an ISIN code.
protected int	weightedValue(int charValue, int leftPos, int rightPos) Calculates the weighted value of a charcter in the code at a specified position.

Methods inherited from class org.apache.commons.validator.routines.checkdigit.ModulusCheckDigit

calculate, getModulus, isValid, sumDigits, toCheckDigit, toInt

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ISIN_CHECK_DIGIT

public static final CheckDigit ISIN_CHECK_DIGIT

Singleton ISIN Check Digit instance

Constructor Detail

ISINCheckDigit

public ISINCheckDigit()

Construct an ISIN Indetifier Check Digit routine.

Method Detail

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 ISIN (from right to left) odd digits are weighted with a factor of one and even digits with a factor of two. Weighted values are reduced to their digital root

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 position of the character in the code, counting from right to left

Returns:

The weighted value of the character.