org.apache.commons.validator.routines.checkdigit

Class ISSNCheckDigit

java.lang.Object

org.apache.commons.validator.routines.checkdigit.ModulusCheckDigit

org.apache.commons.validator.routines.checkdigit.ISSNCheckDigit

All Implemented Interfaces:

Serializable, CheckDigit

public final class ISSNCheckDigit
extends ModulusCheckDigit

International Standard Serial Number (ISSN) is an eight-digit serial number used to uniquely identify a serial publication.

 
 The format is:
 
 ISSN dddd-dddC
 where:
 d = decimal digit (0-9)
 C = checksum (0-9 or X)
 
 The checksum is formed by adding the first 7 digits multiplied by
 the position in the entire number (counting from the right).
 For example, abcd-efg would be 8a + 7b + 6c + 5d + 4e +3f +2g.
 The check digit is modulus 11, where the value 10 is represented by 'X'
 For example:
 ISSN 0317-8471
 ISSN 1050-124X
 

Note: This class expects the input to be numeric only, with all formatting removed. For example:

 03178471
 1050124X
 

Since:

1.5.0

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static CheckDigit	ISSN_CHECK_DIGIT Singleton ISSN Check Digit instance

Constructor Summary

Constructors

Constructor and Description
ISSNCheckDigit() Creates the instance using a checkdigit modulus of 11

Method Summary

Modifier and Type	Method and Description
protected String	toCheckDigit(int charValue) Convert an integer value to a check digit.
protected int	toInt(char character, int leftPos, int rightPos) Convert a character at a specified position to an integer value.
protected int	weightedValue(int charValue, int leftPos, int rightPos) Calculates the weighted value of a character in the code at a specified position.

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

calculate, calculateModulus, getModulus, isValid, sumDigits

Methods inherited from class java.lang.Object

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

Field Detail

ISSN_CHECK_DIGIT

public static final CheckDigit ISSN_CHECK_DIGIT

Singleton ISSN Check Digit instance

Constructor Detail

ISSNCheckDigit

public ISSNCheckDigit()

Creates the instance using a checkdigit modulus of 11

Method Detail

weightedValue

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

Description copied from class: ModulusCheckDigit

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

Some modulus routines weight the value of a character depending on its position in the code (e.g. ISBN-10), while others use different weighting factors for odd/even positions (e.g. EAN or Luhn). Implement the appropriate mechanism required by overriding this method.

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

Throws:

CheckDigitException - if an error occurs calculating the weighted value

toCheckDigit

protected String toCheckDigit(int charValue)
                       throws CheckDigitException

Description copied from class: ModulusCheckDigit

Convert an integer value to a check digit.

Note: this implementation only handles single-digit numeric values For non-numeric characters, override this method to provide integer-->character conversion.

Overrides:

toCheckDigit in class ModulusCheckDigit

Parameters:

charValue - The integer value of the character

Returns:

The converted character

Throws:

CheckDigitException - if integer character value doesn't represent a numeric character

toInt

protected int toInt(char character,
                    int leftPos,
                    int rightPos)
             throws CheckDigitException

Description copied from class: ModulusCheckDigit

Convert a character at a specified position to an integer value.

Note: this implementation only handlers numeric values For non-numeric characters, override this method to provide character-->integer conversion.

Overrides:

toInt in class ModulusCheckDigit

Parameters:

character - The character to convert

leftPos - The position of the character in the code, counting from left to right (for identifiying the position in the string)

rightPos - The position of the character in the code, counting from right to left (not used here)

Returns:

The integer value of the character

Throws:

CheckDigitException - if character is non-numeric