org.apache.commons.validator.routines.checkdigit
Interface CheckDigit

All Known Implementing Classes:
EAN13CheckDigit, ISBN10CheckDigit, ISBNCheckDigit, LuhnCheckDigit, ModulusCheckDigit, VerhoeffCheckDigit

public interface CheckDigit

Check Digit calculation and validation.

The logic for validating check digits has previously been embedded within the logic for specific code validation, which includes other validations such as verifying the format or length of a code. CheckDigit provides for separating out the check digit calculation logic enabling it to be more easily tested and reused.

Although Commons Validator is primarily concerned with validation, CheckDigit also defines behaviour for calculating/generating check digits, since it makes sense that users will want to (re-)use the same logic for both. The ISBNValidator makes specific use of this feature by providing the facility to validate ISBN-10 codes and then convert them to the new ISBN-13 standard.

CheckDigit is used by the new generic CodeValidator implementation.

Implementations

See the Package Summary for a full list of implementations provided within Commons Validator.

Since:
Validator 1.4
Version:
$Revision: 589328 $ $Date: 2007-10-28 11:43:47 +0100 (So, 28. Okt 2007) $
See Also:
CodeValidator

Method Summary
 String calculate(String code)
          Calculate the Check Digit for a code.
 boolean isValid(String code)
          Validate the check digit for the code.
 

Method Detail

calculate

String calculate(String code)
                 throws CheckDigitException
Calculate the Check Digit for a code.

Parameters:
code - The code to calculate the Check Digit for.
Returns:
The calculated Check Digit
Throws:
CheckDigitException - if an error occurs.

isValid

boolean isValid(String code)
Validate the check digit for the code.

Parameters:
code - The code to validate.
Returns:
true if the check digit is valid, otherwise false.


Copyright © 2002-2010 Apache Software Foundation. All Rights Reserved.