org.egov.infra.utils

Class MoneyUtils

java.lang.Object

org.egov.infra.utils.MoneyUtils

public class MoneyUtils
extends Object

Utility methods for money manipulation.

Author:

Sunil D'Monte

Constructor Summary

Constructors

Constructor and Description
MoneyUtils()

Method Summary

Modifier and Type	Method and Description
static BigDecimal[]	allocate(BigDecimal amountInRupees, long[] weights) This variant of the allocate method allows the original amount to be input as a rupee amount i.e.
static long[]	allocate(long amountInPaise, long[] weights) Splits up an amount into multiple amounts according to the specified weightage.
static boolean	isInteger(String str)
static long	roundAndConvertToPaise(BigDecimal rupees) Converts a rupee amount in BigDecimal to a paise amount as an integer (long).
static BigDecimal	roundOff(BigDecimal amount) This method is a utility method, which takes a BigDecimal and rounds that to 0 places.
static BigDecimal	roundOffTwo(BigDecimal amount) Round off to two decimal big decimal value.

Methods inherited from class java.lang.Object

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

Constructor Detail

MoneyUtils

public MoneyUtils()

Method Detail

allocate

public static long[] allocate(long amountInPaise,
                              long[] weights)

Splits up an amount into multiple amounts according to the specified weightage.

E.g. An amount of 100 and weights (3, 7) will give (30, 70).

The algorithm used is the one described at http://nida.se/patterns/poeaa/money.html. It guarantees that the sum of the splits will exactly equal the input amount, even for fractional cases:

E.g. An amount of 100 and weights (3, 8) will give (28, 72).

In such cases, the individual split amounts might not exactly match the number you'd get from floating-point calculation (27.272 and 72.727 in the example above). With the input amount in paise, the individual split amounts will be at most 1 paisa off.

It is the job of the caller to do the "massaging" of rupee amounts into paise amounts, and vice-versa for the output.

See the unit tests for more examples.

Parameters:

amountInPaise - Has to be whole number, so if your amount is Rs. 100.342, you'll have to convert that to 10034 paise.

weights - Numbers that specify the weight given to each split. They need not add up to 100% (e.g. 3, 3, 4) - any arbitrary weights will do. Also note that (2, 10, 16) is identical to (1, 5, 8).

Returns:

The split amounts. If no weights or a single weight is input, the input amount will be returned.

allocate

public static BigDecimal[] allocate(BigDecimal amountInRupees,
                                    long[] weights)

This variant of the allocate method allows the original amount to be input as a rupee amount i.e. as a BigDecimal, and receive the output splits as BigDecimal amounts too. If the input amount is more than 2 decimal places e.g. Rs. 150.632, it gets rounded to 2 decimal places (using "half-up" rounding) and it is the rounded amount that gets allocated.

Parameters:

amountInRupees -

weights -

Returns:

The splits, also as BigDecimals i.e. rupee amounts. Returns null if the input amount is null. If no weights or a single weight is input, the input amount will be returned.

roundAndConvertToPaise

public static long roundAndConvertToPaise(BigDecimal rupees)

Converts a rupee amount in BigDecimal to a paise amount as an integer (long). E.g. 150 -> 15000 150.23 -> 15023 150.234 -> 15023 150.235 -> 15024 150.236 -> 15024

Parameters:

rupees -

Returns:

roundOffTwo

public static BigDecimal roundOffTwo(BigDecimal amount)

Round off to two decimal big decimal value.

Parameters:

amount - the amount

Returns:

the big decimal

roundOff

public static BigDecimal roundOff(BigDecimal amount)

This method is a utility method, which takes a BigDecimal and rounds that to 0 places.

Parameters:

amount - the amount

Returns:

BigDecimal rounded off to 0 places

isInteger

public static boolean isInteger(String str)