Package org.apache.bval.extras.constraints.checkdigit

Class ABANumberValidator

java.lang.Object

org.apache.bval.extras.constraints.checkdigit.ABANumberValidator

All Implemented Interfaces:

javax.validation.ConstraintValidator<ABANumber,CharSequence>

public final class ABANumberValidator
extends Object

Modulus 10 ABA Number (or Routing Transit Number (RTN)) Check Digit calculation/validation.

ABA Numbers (or Routing Transit Numbers) are a nine digit numeric code used to identify American financial institutions for things such as checks or deposits (ABA stands for the American Bankers Association).

Check digit calculation is based on modulus 10 with digits being weighted based on their position (from right to left) as follows:

• Digits 1, 4 and & 7 are weighted 1
• Digits 2, 5 and & 8 are weighted 7
• Digits 3, 6 and & 9 are weighted 3

For further information see Wikipedia - Routing transit number.

Constructor Summary

Constructors

Constructor	Description
ABANumberValidator()

Method Summary

Modifier and Type	Method	Description
void	initialize(A annotation)
boolean	isValid(CharSequence code, javax.validation.ConstraintValidatorContext context)
protected static int	sumDigits(int number)	Add together the individual digits in a number.
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 java.lang.Object

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

Constructor Detail

ABANumberValidator

public ABANumberValidator()

Method Detail

weightedValue

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

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

ABA Routing numbers are weighted in the following manner:

     left position: 1  2  3  4  5  6  7  8  9
            weight: 3  7  1  3  7  1  3  7  1
 

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.

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

Throws:

Exception

initialize

public final void initialize(A annotation)

Specified by:

initialize in interface javax.validation.ConstraintValidator<A extends Annotation,CharSequence>

isValid

public boolean isValid(CharSequence code,
                       javax.validation.ConstraintValidatorContext context)

Specified by:

isValid in interface javax.validation.ConstraintValidator<A extends Annotation,CharSequence>

toInt

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

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.

Parameters:

character - The character to convert

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 integer value of the character

sumDigits

protected static int sumDigits(int number)

Add together the individual digits in a number.

Parameters:

number - The number whose digits are to be added

Returns:

The sum of the digits