Class ABANumberCheckDigit

  • All Implemented Interfaces:
    java.io.Serializable, CheckDigit

    public final class ABANumberCheckDigit
    extends ModulusCheckDigit
    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.

    Since:
    Validator 1.4
    Version:
    $Revision: 1649191 $
    See Also:
    Serialized Form
    • Field Detail

      • ABAN_CHECK_DIGIT

        public static final CheckDigit ABAN_CHECK_DIGIT
        Singleton Routing Transit Number Check Digit instance
      • POSITION_WEIGHT

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

      • ABANumberCheckDigit

        public ABANumberCheckDigit()
        Construct a modulus 10 Check Digit routine for ABA Numbers.
    • Method Detail

      • weightedValue

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