org.josef.finance

Class UKBankAccountNumber

java.lang.Object

org.josef.finance.UKBankAccountNumber

public final class UKBankAccountNumber
extends Object

Utility class to verify UK Bank Account Numbers.
See: http://www.vocalink.com/products/payments/customer-support-services/modulus-checking.aspx
Note: This class only performs some basic validation and is not meant for production environments. It has the following limitations:

1. Is not aware of the fact if an account is actually being used
2. Does not handle accounts longer than 8 digits properly
3. Does not handle all exceptions

Despite its limitations it is suitable for demonstration purposes and it will properly verify:

1. The account consists of digits only
2. The account is not too short
3. The account is not too long
4. The account using the correct sort code range and the proper modulo method and correct weights
5. The second algorithm is taken into account when the first algorithm fails
6. Algorithms with exceptions 1 and 5

Version:

1.0 $Revision: 6488 $

Author:

Kees Schotanus

Field Summary

Fields

Modifier and Type	Field and Description
static String	DOES_NOT_PASS_MODULO_CHECK_MSG Sort code/Bank account number do not pass modulo check message.
static String	INVALID_LENGTH_MSG Bank account number has invalid length message.
static int	MINIMUM_LENGTH The minimum length of a bank account number.
static String	NOT_NUMERIC_MSG Bank account number is not numeric message.
static int	STANDARD_LENGTH The standard length (length used for validation) of a bank account number.

Method Summary

Modifier and Type	Method and Description
static void	checkBankAccountNumber(String bankAccountNumber) Determines whether the supplied bankAccountNumber combination is valid.
static void	checkSortCodeAndBankAccountNumber(String sortCode, String bankAccountNumber) Determines whether the supplied sortCode and bankAccountNumber combination is valid.
static void	main(String[] args) For test purpose only.

Methods inherited from class java.lang.Object

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

Field Detail

STANDARD_LENGTH

public static final int STANDARD_LENGTH

The standard length (length used for validation) of a bank account number.

See Also:

Constant Field Values

MINIMUM_LENGTH

public static final int MINIMUM_LENGTH

The minimum length of a bank account number.

See Also:

Constant Field Values

INVALID_LENGTH_MSG

public static final String INVALID_LENGTH_MSG

Bank account number has invalid length message.

See Also:

Constant Field Values

NOT_NUMERIC_MSG

public static final String NOT_NUMERIC_MSG

Bank account number is not numeric message.

See Also:

Constant Field Values

DOES_NOT_PASS_MODULO_CHECK_MSG

public static final String DOES_NOT_PASS_MODULO_CHECK_MSG

Sort code/Bank account number do not pass modulo check message.

See Also:

Constant Field Values

Method Detail

checkBankAccountNumber

public static void checkBankAccountNumber(String bankAccountNumber)
                                   throws InvalidArgumentException

Determines whether the supplied bankAccountNumber combination is valid.
A bank account number is valid when:

• It is numeric
• Has a length of 6 to 8 characters (inclusive)

Note: This method does NOT validate that the supplied bankAccountNumber is an actually used account, nor does it perform any additional validation since this is impossible to do without a sort code.

Parameters:

bankAccountNumber - The bank account number.

Throws:

InvalidArgumentException - When the supplied bankAccountNumber combination is invalid.

checkSortCodeAndBankAccountNumber

public static void checkSortCodeAndBankAccountNumber(String sortCode,
                                                     String bankAccountNumber)
                                              throws InvalidArgumentException

Determines whether the supplied sortCode and bankAccountNumber combination is valid.
A bank account number is valid when:

• It is numeric
• Has a length of 6 to 8 characters (inclusive)
• The sort code has no corresponding UKSortCodeRange
• The sort code does have a corresponding UKSortCodeRange and passes the modulo test(s)

Parameters:

sortCode - The sort code.

bankAccountNumber - The bank account number.

Throws:

InvalidArgumentException - When the supplied sort code/bank account number combination is invalid.

main

public static void main(String[] args)
                 throws InvalidArgumentException

For test purpose only.

Parameters:

args - Not used.

Throws:

InvalidArgumentException - When validation fails.