work on fixing interest calculation for declining balance loans.
This commit is contained in:
Keith Woodlock
@@ -11,7 +11,7 @@ public class CurrencyData implements Serializable {
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private final String nameCode;
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private final String displayLabel;
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public CurrencyData(final String code, final String name, final int decimalPlaces, String displaySymbol, String nameCode) {
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public CurrencyData(final String code, final String name, final int decimalPlaces, final String displaySymbol, final String nameCode) {
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this.code = code;
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this.name = name;
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this.decimalPlaces = decimalPlaces;
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+19
@@ -0,0 +1,19 @@
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package org.mifosng.platform.loanschedule.domain;
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import java.math.BigDecimal;
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import java.util.List;
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import org.joda.time.LocalDate;
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import org.mifosng.platform.api.data.CurrencyData;
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import org.mifosng.platform.api.data.LoanSchedule;
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import org.mifosng.platform.loan.domain.LoanProductRelatedDetail;
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public interface AmortizationLoanScheduleGenerator {
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LoanSchedule generate(LoanProductRelatedDetail loanScheduleInfo, LocalDate disbursementDate,
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LocalDate firstRepaymentDate, LocalDate interestCalculatedFrom, CurrencyData currencyData,
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BigDecimal periodInterestRateForRepaymentPeriod,
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LocalDate idealDisbursementDateBasedOnFirstRepaymentDate,
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List<LocalDate> scheduledDates);
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}
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+27
-106
@@ -1,7 +1,6 @@
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package org.mifosng.platform.loanschedule.domain;
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import java.math.BigDecimal;
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import java.math.RoundingMode;
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import java.util.ArrayList;
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import java.util.List;
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@@ -13,16 +12,31 @@ import org.mifosng.platform.api.data.MoneyData;
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import org.mifosng.platform.api.data.ScheduledLoanInstallment;
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import org.mifosng.platform.currency.domain.MonetaryCurrency;
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import org.mifosng.platform.currency.domain.Money;
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import org.mifosng.platform.loan.domain.AmortizationMethod;
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import org.mifosng.platform.loan.domain.LoanProductRelatedDetail;
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import org.mifosng.platform.loan.domain.PeriodFrequencyType;
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public class DecliningBalanceMethodLoanScheduleGenerator implements
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LoanScheduleGenerator {
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/**
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* <p>
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* Declining balance can amortized (see {@link AmortizationMethod}) in two ways at present:
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* <ol><li>Equal principal payments</li><li>Equal installment payments</li></ol>
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* </p>
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*
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* <p>
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* When amortized using <i>equal principal payments</i>, the <b>principal component</b> of each installment is fixed and <b>interest due</b>
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* is calculated from the <b>outstanding principal balance</b> resulting in a different <b>total payment due</b> for each installment.
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* </p>
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*
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* <p>
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* When amortized using <i>equal installments</i>, the <b>total payment due</b> for each installment is fixed and
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* is calculated using the excel like <code>pmt</code> function. The <b>interest due</b> is calculated from the <b>outstanding principal balance</b>
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* which results in a <b>principal component</b> that is <b>total payment due</b> minus <b>interest due</b>.
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* </p>
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*/
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public class DecliningBalanceMethodLoanScheduleGenerator implements LoanScheduleGenerator {
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private final ScheduledDateGenerator scheduledDateGenerator = new DefaultScheduledDateGenerator();
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private final PaymentPeriodsInOneYearCalculator paymentPeriodsInOneYearCalculator = new DefaultPaymentPeriodsInOneYearCalculator();
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private final PeriodicInterestRateCalculator periodicInterestRateCalculator = new PeriodicInterestRateCalculator();
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private final PmtCalculator pmtCalculator = new PmtCalculator();
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@Override
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public LoanSchedule generate(
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@@ -31,114 +45,21 @@ public class DecliningBalanceMethodLoanScheduleGenerator implements
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final PeriodFrequencyType loanTermFrequencyType,
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final LocalDate disbursementDate,
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final LocalDate firstRepaymentDate,
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final LocalDate interestCalculatedFrom, CurrencyData currencyData) {
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List<ScheduledLoanInstallment> scheduledLoanInstallments = new ArrayList<ScheduledLoanInstallment>();
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final LocalDate interestCalculatedFrom,
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final CurrencyData currencyData) {
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// 1. generate valid set of 'due dates' based on some of the 'loan attributes'
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List<LocalDate> scheduledDates = this.scheduledDateGenerator.generate(loanScheduleInfo, disbursementDate, firstRepaymentDate);
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LocalDate idealDisbursementDateBasedOnFirstRepaymentDate = this.scheduledDateGenerator.idealDisbursementDateBasedOnFirstRepaymentDate(loanScheduleInfo, scheduledDates);
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// 2. determine the 'periodic' interest rate based on the 'repayment periods' so we can use
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final BigDecimal periodInterestRateForRepaymentPeriod = this.periodicInterestRateCalculator.calculateFrom(loanScheduleInfo);
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// 3. determine 'total payment' for each repayment based on pmt function (and hence the total due overall)
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final MonetaryCurrency monetaryCurrency = loanScheduleInfo.getPrincipal().getCurrency();
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Money totalDuePerInstallment = this.pmtCalculator.calculatePaymentForOnePeriodFrom(loanScheduleInfo, periodInterestRateForRepaymentPeriod, monetaryCurrency);
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// final Money totalDue = this.pmtCalculator.calculateTotalRepaymentFrom(loanScheduleInfo, periodInterestRateForRepaymentPeriod, monetaryCurrency);
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// REVIEW. calculate total interest due based on loan term settings rather than inferring loan term from regular repayment schedule
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final BigDecimal periodInterestRateForLoanTermPeriod = this.periodicInterestRateCalculator.calculateFrom(loanTermFrequencyType, loanScheduleInfo.getAnnualNominalInterestRate());
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final Money totalRepaymentDueForLoanTerm = this.pmtCalculator.calculateTotalRepaymentFrom(loanScheduleInfo.getPrincipal(), loanTermFrequency, periodInterestRateForLoanTermPeriod, monetaryCurrency);
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totalDuePerInstallment = totalRepaymentDueForLoanTerm.dividedBy(loanScheduleInfo.getNumberOfRepayments(), RoundingMode.HALF_EVEN);
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Money totalInterestDue = totalRepaymentDueForLoanTerm.minus(loanScheduleInfo.getPrincipal());
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Money outstandingBalance = loanScheduleInfo.getPrincipal();
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Money totalPrincipal = Money.zero(monetaryCurrency);
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Money totalInterest = Money.zero(monetaryCurrency);
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LocalDate idealDisbursementDateBasedOnFirstRepaymentDate = this.scheduledDateGenerator.idealDisbursementDateBasedOnFirstRepaymentDate(loanScheduleInfo, scheduledDates);
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double interestCalculationGraceOnRepaymentPeriodFraction = this.paymentPeriodsInOneYearCalculator.calculateRepaymentPeriodAsAFractionOfDays(loanScheduleInfo.getRepaymentPeriodFrequencyType(),
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loanScheduleInfo.getRepayEvery(), interestCalculatedFrom, scheduledDates, idealDisbursementDateBasedOnFirstRepaymentDate);
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LocalDate startDate = disbursementDate;
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int installmentNumber = 1;
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for (LocalDate scheduledDueDate : scheduledDates) {
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// number of days from startDate to this scheduledDate
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int daysInPeriod = Days.daysBetween(startDate.toDateMidnight().toDateTime(), scheduledDueDate.toDateMidnight().toDateTime()).getDays();
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// TODO - total interest for loan is calculated using loan term settings (loanTermFrequency & loanTermFrequencyType)
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// - its possible that the 'repyament schedule' is irregular in which case the interest for the installment might not be the periodic interest rate
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// - but infact somethink like twice it e.g. 4 month installment followed by 2 month installment followed by 1 month installment
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// - the below doesnt really support highly irregular loan schedules and this case needs to be looked at.
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Money interestForInstallment = this.periodicInterestRateCalculator.calculateInterestOn(outstandingBalance, periodInterestRateForRepaymentPeriod, daysInPeriod, loanScheduleInfo);
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Money principalForInstallment = this.periodicInterestRateCalculator.calculatePrincipalOn(totalDuePerInstallment, interestForInstallment, loanScheduleInfo);
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if (interestCalculationGraceOnRepaymentPeriodFraction >= Integer.valueOf(1).doubleValue()) {
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Money graceOnInterestForRepaymentPeriod = interestForInstallment;
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interestForInstallment = interestForInstallment.minus(graceOnInterestForRepaymentPeriod);
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totalInterestDue = totalInterestDue.minus(graceOnInterestForRepaymentPeriod);
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interestCalculationGraceOnRepaymentPeriodFraction = interestCalculationGraceOnRepaymentPeriodFraction - Integer.valueOf(1).doubleValue();
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} else if (interestCalculationGraceOnRepaymentPeriodFraction > Double.valueOf("0.25") && interestCalculationGraceOnRepaymentPeriodFraction < Integer.valueOf(1).doubleValue()) {
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Money graceOnInterestForRepaymentPeriod = interestForInstallment.multipliedBy(interestCalculationGraceOnRepaymentPeriodFraction);
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interestForInstallment = interestForInstallment.minus(graceOnInterestForRepaymentPeriod);
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totalInterestDue = totalInterestDue.minus(graceOnInterestForRepaymentPeriod);
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interestCalculationGraceOnRepaymentPeriodFraction = Double.valueOf("0");
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}
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totalPrincipal = totalPrincipal.plus(principalForInstallment);
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totalInterest = totalInterest.plus(interestForInstallment);
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if (installmentNumber == loanScheduleInfo.getNumberOfRepayments()) {
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Money principalDifference = totalPrincipal.minus(loanScheduleInfo.getPrincipal());
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if (principalDifference.isLessThanZero()) {
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principalForInstallment = principalForInstallment.plus(principalDifference.abs());
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} else if (principalDifference.isGreaterThanZero()) {
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principalForInstallment = principalForInstallment.minus(principalDifference.abs());
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}
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final Money interestDifference = totalInterest.minus(totalInterestDue);
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if (interestDifference.isLessThanZero()) {
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interestForInstallment = interestForInstallment.plus(interestDifference.abs());
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} else if (interestDifference.isGreaterThanZero()) {
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interestForInstallment = interestForInstallment.minus(interestDifference.abs());
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}
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// if (loanScheduleInfo.getAmortizationMethod().equals(AmortizationMethod.EQUAL_INSTALLMENTS)) {
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// Money interestDifference = totalInterest.minus(totalInterestDue);
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// if (interestDifference.isLessThanZero()) {
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// interestForInstallment = interestForInstallment.plus(interestDifference.abs());
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// } else if (interestDifference.isGreaterThanZero()) {
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// interestForInstallment = interestForInstallment.minus(interestDifference.abs());
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// }
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// }
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}
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Money totalInstallmentDue = principalForInstallment.plus(interestForInstallment);
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outstandingBalance = outstandingBalance.minus(principalForInstallment);
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MoneyData principalPerInstallmentValue = MoneyData.of(currencyData, principalForInstallment.getAmount());
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MoneyData interestPerInstallmentValue = MoneyData.of(currencyData, interestForInstallment.getAmount());
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MoneyData totalInstallmentDueValue = MoneyData.of(currencyData, totalInstallmentDue.getAmount());
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MoneyData outstandingBalanceValue = MoneyData.of(currencyData, outstandingBalance.getAmount());
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ScheduledLoanInstallment installment = new ScheduledLoanInstallment(
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Integer.valueOf(installmentNumber), startDate,
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scheduledDueDate, principalPerInstallmentValue,
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interestPerInstallmentValue,
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totalInstallmentDueValue,
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outstandingBalanceValue);
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scheduledLoanInstallments.add(installment);
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startDate = scheduledDueDate;
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installmentNumber++;
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}
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return new LoanSchedule(scheduledLoanInstallments);
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// Determine with 'amortisation' approach to use
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AmortizationLoanScheduleGenerator generator = new EqualInstallmentsAmortizationLoanScheduleGenerator();
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return generator.generate(loanScheduleInfo, disbursementDate, firstRepaymentDate, interestCalculatedFrom, currencyData,
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periodInterestRateForRepaymentPeriod, idealDisbursementDateBasedOnFirstRepaymentDate, scheduledDates);
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}
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/**
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+114
@@ -0,0 +1,114 @@
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package org.mifosng.platform.loanschedule.domain;
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import java.math.BigDecimal;
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import java.util.ArrayList;
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import java.util.List;
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import org.joda.time.Days;
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import org.joda.time.LocalDate;
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import org.mifosng.platform.api.data.CurrencyData;
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import org.mifosng.platform.api.data.LoanSchedule;
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import org.mifosng.platform.api.data.MoneyData;
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import org.mifosng.platform.api.data.ScheduledLoanInstallment;
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import org.mifosng.platform.currency.domain.MonetaryCurrency;
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import org.mifosng.platform.currency.domain.Money;
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import org.mifosng.platform.loan.domain.LoanProductRelatedDetail;
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public class EqualInstallmentsAmortizationLoanScheduleGenerator implements AmortizationLoanScheduleGenerator {
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private final PeriodicInterestRateCalculator periodicInterestRateCalculator = new PeriodicInterestRateCalculator();
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private final PaymentPeriodsInOneYearCalculator paymentPeriodsInOneYearCalculator = new DefaultPaymentPeriodsInOneYearCalculator();
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private final PmtCalculator pmtCalculator = new PmtCalculator();
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@Override
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public LoanSchedule generate(final LoanProductRelatedDetail loanScheduleInfo,
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final LocalDate disbursementDate,
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final LocalDate firstRepaymentDate,
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final LocalDate interestCalculatedFrom,
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final CurrencyData currencyData,
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final BigDecimal periodInterestRateForRepaymentPeriod,
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final LocalDate idealDisbursementDateBasedOnFirstRepaymentDate,
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final List<LocalDate> scheduledDates) {
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List<ScheduledLoanInstallment> scheduledLoanInstallments = new ArrayList<ScheduledLoanInstallment>();
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// 3. determine 'total payment' for each repayment based on pmt function (and hence the total due overall)
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final MonetaryCurrency monetaryCurrency = loanScheduleInfo.getPrincipal().getCurrency();
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Money totalDuePerInstallment = this.pmtCalculator.calculatePaymentForOnePeriodFrom(loanScheduleInfo, periodInterestRateForRepaymentPeriod, monetaryCurrency);
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final Money totalRepaymentDueForLoanTerm = this.pmtCalculator.calculateTotalRepaymentFrom(loanScheduleInfo, periodInterestRateForRepaymentPeriod, monetaryCurrency);
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Money totalInterestDue = totalRepaymentDueForLoanTerm.minus(loanScheduleInfo.getPrincipal());
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Money outstandingBalance = loanScheduleInfo.getPrincipal();
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Money totalPrincipal = Money.zero(monetaryCurrency);
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Money totalInterest = Money.zero(monetaryCurrency);
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double interestCalculationGraceOnRepaymentPeriodFraction = this.paymentPeriodsInOneYearCalculator.calculateRepaymentPeriodAsAFractionOfDays(loanScheduleInfo.getRepaymentPeriodFrequencyType(),
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loanScheduleInfo.getRepayEvery(), interestCalculatedFrom, scheduledDates, idealDisbursementDateBasedOnFirstRepaymentDate);
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LocalDate startDate = disbursementDate;
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int installmentNumber = 1;
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for (LocalDate scheduledDueDate : scheduledDates) {
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// number of days from startDate to this scheduledDate
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int daysInPeriod = Days.daysBetween(startDate.toDateMidnight().toDateTime(), scheduledDueDate.toDateMidnight().toDateTime()).getDays();
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Money interestForInstallment = this.periodicInterestRateCalculator.calculateInterestOn(outstandingBalance, periodInterestRateForRepaymentPeriod, daysInPeriod, loanScheduleInfo);
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Money principalForInstallment = this.periodicInterestRateCalculator.calculatePrincipalOn(totalDuePerInstallment, interestForInstallment, loanScheduleInfo);
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if (interestCalculationGraceOnRepaymentPeriodFraction >= Integer.valueOf(1).doubleValue()) {
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Money graceOnInterestForRepaymentPeriod = interestForInstallment;
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interestForInstallment = interestForInstallment.minus(graceOnInterestForRepaymentPeriod);
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totalInterestDue = totalInterestDue.minus(graceOnInterestForRepaymentPeriod);
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interestCalculationGraceOnRepaymentPeriodFraction = interestCalculationGraceOnRepaymentPeriodFraction - Integer.valueOf(1).doubleValue();
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} else if (interestCalculationGraceOnRepaymentPeriodFraction > Double.valueOf("0.25") && interestCalculationGraceOnRepaymentPeriodFraction < Integer.valueOf(1).doubleValue()) {
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Money graceOnInterestForRepaymentPeriod = interestForInstallment.multipliedBy(interestCalculationGraceOnRepaymentPeriodFraction);
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interestForInstallment = interestForInstallment.minus(graceOnInterestForRepaymentPeriod);
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totalInterestDue = totalInterestDue.minus(graceOnInterestForRepaymentPeriod);
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interestCalculationGraceOnRepaymentPeriodFraction = Double.valueOf("0");
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}
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totalPrincipal = totalPrincipal.plus(principalForInstallment);
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totalInterest = totalInterest.plus(interestForInstallment);
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if (installmentNumber == loanScheduleInfo.getNumberOfRepayments()) {
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Money principalDifference = totalPrincipal.minus(loanScheduleInfo.getPrincipal());
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if (principalDifference.isLessThanZero()) {
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principalForInstallment = principalForInstallment.plus(principalDifference.abs());
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} else if (principalDifference.isGreaterThanZero()) {
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principalForInstallment = principalForInstallment.minus(principalDifference.abs());
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}
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final Money interestDifference = totalInterest.minus(totalInterestDue);
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if (interestDifference.isLessThanZero()) {
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interestForInstallment = interestForInstallment.plus(interestDifference.abs());
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} else if (interestDifference.isGreaterThanZero()) {
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interestForInstallment = interestForInstallment.minus(interestDifference.abs());
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}
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}
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Money totalInstallmentDue = principalForInstallment.plus(interestForInstallment);
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outstandingBalance = outstandingBalance.minus(principalForInstallment);
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MoneyData principalPerInstallmentValue = MoneyData.of(currencyData, principalForInstallment.getAmount());
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MoneyData interestPerInstallmentValue = MoneyData.of(currencyData, interestForInstallment.getAmount());
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MoneyData totalInstallmentDueValue = MoneyData.of(currencyData, totalInstallmentDue.getAmount());
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MoneyData outstandingBalanceValue = MoneyData.of(currencyData, outstandingBalance.getAmount());
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ScheduledLoanInstallment installment = new ScheduledLoanInstallment(
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Integer.valueOf(installmentNumber), startDate,
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scheduledDueDate, principalPerInstallmentValue,
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interestPerInstallmentValue,
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totalInstallmentDueValue,
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outstandingBalanceValue);
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scheduledLoanInstallments.add(installment);
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startDate = scheduledDueDate;
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installmentNumber++;
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}
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return new LoanSchedule(scheduledLoanInstallments);
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}
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}
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+133
@@ -0,0 +1,133 @@
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package org.mifosng.platform.loanschedule.domain;
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import java.math.BigDecimal;
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import java.util.ArrayList;
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import java.util.List;
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import org.joda.time.Days;
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import org.joda.time.LocalDate;
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import org.mifosng.platform.api.data.CurrencyData;
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import org.mifosng.platform.api.data.LoanSchedule;
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import org.mifosng.platform.api.data.MoneyData;
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import org.mifosng.platform.api.data.ScheduledLoanInstallment;
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import org.mifosng.platform.currency.domain.MonetaryCurrency;
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import org.mifosng.platform.currency.domain.Money;
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import org.mifosng.platform.loan.domain.LoanProductRelatedDetail;
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public class EqualInstallmentsWithIrregularRepaymentScheduleAmortizationLoanScheduleGenerator implements AmortizationLoanScheduleGenerator {
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private final PeriodicInterestRateCalculator periodicInterestRateCalculator = new PeriodicInterestRateCalculator();
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private final PaymentPeriodsInOneYearCalculator paymentPeriodsInOneYearCalculator = new DefaultPaymentPeriodsInOneYearCalculator();
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private final PmtCalculator pmtCalculator = new PmtCalculator();
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@Override
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public LoanSchedule generate(final LoanProductRelatedDetail loanScheduleInfo,
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final LocalDate disbursementDate,
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final LocalDate firstRepaymentDate,
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final LocalDate interestCalculatedFrom,
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final CurrencyData currencyData,
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final BigDecimal periodInterestRateForRepaymentPeriod,
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final LocalDate idealDisbursementDateBasedOnFirstRepaymentDate,
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final List<LocalDate> scheduledDates) {
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List<ScheduledLoanInstallment> scheduledLoanInstallments = new ArrayList<ScheduledLoanInstallment>();
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// 3. determine 'total payment' for each repayment based on pmt function (and hence the total due overall)
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final MonetaryCurrency monetaryCurrency = loanScheduleInfo.getPrincipal().getCurrency();
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Money totalDuePerInstallment = this.pmtCalculator.calculatePaymentForOnePeriodFrom(loanScheduleInfo, periodInterestRateForRepaymentPeriod, monetaryCurrency);
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final Money totalRepaymentDueForLoanTerm = this.pmtCalculator.calculateTotalRepaymentFrom(loanScheduleInfo, periodInterestRateForRepaymentPeriod, monetaryCurrency);
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// REVIEW. calculate total interest due based on loan term settings rather than inferring loan term from regular repayment schedule
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// final BigDecimal periodInterestRateForLoanTermPeriod = this.periodicInterestRateCalculator.calculateFrom(loanTermFrequencyType, loanScheduleInfo.getAnnualNominalInterestRate());
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// final Money totalRepaymentDueForLoanTerm = this.pmtCalculator.calculateTotalRepaymentFrom(loanScheduleInfo.getPrincipal(), loanTermFrequency, periodInterestRateForLoanTermPeriod, monetaryCurrency);
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// totalDuePerInstallment = totalRepaymentDueForLoanTerm.dividedBy(loanScheduleInfo.getNumberOfRepayments(), RoundingMode.HALF_EVEN);
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Money totalInterestDue = totalRepaymentDueForLoanTerm.minus(loanScheduleInfo.getPrincipal());
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Money outstandingBalance = loanScheduleInfo.getPrincipal();
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Money totalPrincipal = Money.zero(monetaryCurrency);
|
||||
Money totalInterest = Money.zero(monetaryCurrency);
|
||||
|
||||
double interestCalculationGraceOnRepaymentPeriodFraction = this.paymentPeriodsInOneYearCalculator.calculateRepaymentPeriodAsAFractionOfDays(loanScheduleInfo.getRepaymentPeriodFrequencyType(),
|
||||
loanScheduleInfo.getRepayEvery(), interestCalculatedFrom, scheduledDates, idealDisbursementDateBasedOnFirstRepaymentDate);
|
||||
|
||||
LocalDate startDate = disbursementDate;
|
||||
int installmentNumber = 1;
|
||||
for (LocalDate scheduledDueDate : scheduledDates) {
|
||||
|
||||
// number of days from startDate to this scheduledDate
|
||||
int daysInPeriod = Days.daysBetween(startDate.toDateMidnight().toDateTime(), scheduledDueDate.toDateMidnight().toDateTime()).getDays();
|
||||
|
||||
// TODO - total interest for loan is calculated using loan term settings (loanTermFrequency & loanTermFrequencyType)
|
||||
// - its possible that the 'repyament schedule' is irregular in which case the interest for the installment might not be the periodic interest rate
|
||||
// - but infact somethink like twice it e.g. 4 month installment followed by 2 month installment followed by 1 month installment
|
||||
// - the below doesnt really support highly irregular loan schedules and this case needs to be looked at.
|
||||
Money interestForInstallment = this.periodicInterestRateCalculator.calculateInterestOn(outstandingBalance, periodInterestRateForRepaymentPeriod, daysInPeriod, loanScheduleInfo);
|
||||
Money principalForInstallment = this.periodicInterestRateCalculator.calculatePrincipalOn(totalDuePerInstallment, interestForInstallment, loanScheduleInfo);
|
||||
|
||||
if (interestCalculationGraceOnRepaymentPeriodFraction >= Integer.valueOf(1).doubleValue()) {
|
||||
Money graceOnInterestForRepaymentPeriod = interestForInstallment;
|
||||
interestForInstallment = interestForInstallment.minus(graceOnInterestForRepaymentPeriod);
|
||||
totalInterestDue = totalInterestDue.minus(graceOnInterestForRepaymentPeriod);
|
||||
interestCalculationGraceOnRepaymentPeriodFraction = interestCalculationGraceOnRepaymentPeriodFraction - Integer.valueOf(1).doubleValue();
|
||||
} else if (interestCalculationGraceOnRepaymentPeriodFraction > Double.valueOf("0.25") && interestCalculationGraceOnRepaymentPeriodFraction < Integer.valueOf(1).doubleValue()) {
|
||||
Money graceOnInterestForRepaymentPeriod = interestForInstallment.multipliedBy(interestCalculationGraceOnRepaymentPeriodFraction);
|
||||
interestForInstallment = interestForInstallment.minus(graceOnInterestForRepaymentPeriod);
|
||||
totalInterestDue = totalInterestDue.minus(graceOnInterestForRepaymentPeriod);
|
||||
interestCalculationGraceOnRepaymentPeriodFraction = Double.valueOf("0");
|
||||
}
|
||||
|
||||
totalPrincipal = totalPrincipal.plus(principalForInstallment);
|
||||
totalInterest = totalInterest.plus(interestForInstallment);
|
||||
|
||||
if (installmentNumber == loanScheduleInfo.getNumberOfRepayments()) {
|
||||
Money principalDifference = totalPrincipal.minus(loanScheduleInfo.getPrincipal());
|
||||
if (principalDifference.isLessThanZero()) {
|
||||
principalForInstallment = principalForInstallment.plus(principalDifference.abs());
|
||||
} else if (principalDifference.isGreaterThanZero()) {
|
||||
principalForInstallment = principalForInstallment.minus(principalDifference.abs());
|
||||
}
|
||||
|
||||
final Money interestDifference = totalInterest.minus(totalInterestDue);
|
||||
if (interestDifference.isLessThanZero()) {
|
||||
interestForInstallment = interestForInstallment.plus(interestDifference.abs());
|
||||
} else if (interestDifference.isGreaterThanZero()) {
|
||||
interestForInstallment = interestForInstallment.minus(interestDifference.abs());
|
||||
}
|
||||
|
||||
// if (loanScheduleInfo.getAmortizationMethod().equals(AmortizationMethod.EQUAL_INSTALLMENTS)) {
|
||||
// Money interestDifference = totalInterest.minus(totalInterestDue);
|
||||
// if (interestDifference.isLessThanZero()) {
|
||||
// interestForInstallment = interestForInstallment.plus(interestDifference.abs());
|
||||
// } else if (interestDifference.isGreaterThanZero()) {
|
||||
// interestForInstallment = interestForInstallment.minus(interestDifference.abs());
|
||||
// }
|
||||
// }
|
||||
}
|
||||
|
||||
Money totalInstallmentDue = principalForInstallment.plus(interestForInstallment);
|
||||
|
||||
outstandingBalance = outstandingBalance.minus(principalForInstallment);
|
||||
|
||||
MoneyData principalPerInstallmentValue = MoneyData.of(currencyData, principalForInstallment.getAmount());
|
||||
MoneyData interestPerInstallmentValue = MoneyData.of(currencyData, interestForInstallment.getAmount());
|
||||
MoneyData totalInstallmentDueValue = MoneyData.of(currencyData, totalInstallmentDue.getAmount());
|
||||
MoneyData outstandingBalanceValue = MoneyData.of(currencyData, outstandingBalance.getAmount());
|
||||
|
||||
ScheduledLoanInstallment installment = new ScheduledLoanInstallment(
|
||||
Integer.valueOf(installmentNumber), startDate,
|
||||
scheduledDueDate, principalPerInstallmentValue,
|
||||
interestPerInstallmentValue,
|
||||
totalInstallmentDueValue,
|
||||
outstandingBalanceValue);
|
||||
|
||||
scheduledLoanInstallments.add(installment);
|
||||
|
||||
startDate = scheduledDueDate;
|
||||
|
||||
installmentNumber++;
|
||||
}
|
||||
|
||||
return new LoanSchedule(scheduledLoanInstallments);
|
||||
}
|
||||
}
|
||||
+5
-3
@@ -34,9 +34,11 @@ public class PeriodicInterestRateCalculator {
|
||||
return loanScheduleInfo.getAnnualNominalInterestRate().divide(divisor, mc).multiply(numberOfPeriods);
|
||||
}
|
||||
|
||||
public Money calculateInterestOn(Money outstandingBalance, BigDecimal periodInterestRateForRepaymentPeriod,
|
||||
int daysInPeriod,
|
||||
LoanProductRelatedDetail loanScheduleInfo) {
|
||||
public Money calculateInterestOn(
|
||||
final Money outstandingBalance,
|
||||
final BigDecimal periodInterestRateForRepaymentPeriod,
|
||||
final int daysInPeriod,
|
||||
final LoanProductRelatedDetail loanScheduleInfo) {
|
||||
|
||||
MathContext mc = new MathContext(8, RoundingMode.HALF_EVEN);
|
||||
Money interestDue = Money.zero(outstandingBalance.getCurrency());
|
||||
|
||||
+112
@@ -0,0 +1,112 @@
|
||||
package org.mifosng.platform.loanschedule.domain;
|
||||
|
||||
import static org.hamcrest.CoreMatchers.*;
|
||||
import static org.junit.Assert.*;
|
||||
|
||||
import java.util.List;
|
||||
|
||||
import org.hamcrest.Matcher;
|
||||
import org.joda.time.LocalDate;
|
||||
import org.junit.Before;
|
||||
import org.junit.Test;
|
||||
import org.junit.runner.RunWith;
|
||||
import org.mifosng.platform.api.data.CurrencyData;
|
||||
import org.mifosng.platform.api.data.LoanSchedule;
|
||||
import org.mifosng.platform.api.data.ScheduledLoanInstallment;
|
||||
import org.mifosng.platform.loan.domain.LoanProductRelatedDetail;
|
||||
import org.mifosng.platform.loan.domain.PeriodFrequencyType;
|
||||
import org.mockito.runners.MockitoJUnitRunner;
|
||||
|
||||
@RunWith(MockitoJUnitRunner.class)
|
||||
public class DecliningBalanceMethodLoanScheduleGeneratorTest {
|
||||
|
||||
// class under test
|
||||
private DecliningBalanceMethodLoanScheduleGenerator decliningBalanceGenerator;
|
||||
|
||||
// test doubles
|
||||
private CurrencyData currencyData = null;
|
||||
private LoanProductRelatedDetail loanScheduleInfo = null;
|
||||
|
||||
@Before
|
||||
public void setupForEachTest() {
|
||||
currencyData = new CurrencyData("USD", "US Dollar", 2, "$", "currency.USD");
|
||||
|
||||
decliningBalanceGenerator = new DecliningBalanceMethodLoanScheduleGenerator();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenEqualInstallmentAmortisationShouldCalculatePaymentPerInstallmentUsingPmtFunctionAndDerivePrincipalAndInterestComponents() {
|
||||
|
||||
// setup
|
||||
Integer loanTermFrequency = 12;
|
||||
PeriodFrequencyType loanTermFrequencyType = PeriodFrequencyType.MONTHS;
|
||||
loanScheduleInfo = LoanProductRelatedDetailTestHelper.createSettingsForEqualInstallmentAmortizationQuarterly();
|
||||
|
||||
LocalDate disbursementDate = new LocalDate(2011, 1, 11);
|
||||
LocalDate firstRepaymentDate = new LocalDate(2011, 5, 1);
|
||||
LocalDate interestCalculatedFrom = new LocalDate(2011, 2, 1);
|
||||
|
||||
// pre assertions
|
||||
assertThat(loanTermFrequency, is(loanScheduleInfo.getNumberOfRepayments() * loanScheduleInfo.getRepayEvery()));
|
||||
assertThat(loanTermFrequencyType, is(loanScheduleInfo.getRepaymentPeriodFrequencyType()));
|
||||
|
||||
// exercise test
|
||||
LoanSchedule schedule = decliningBalanceGenerator.generate(loanScheduleInfo, loanTermFrequency, loanTermFrequencyType,
|
||||
disbursementDate, firstRepaymentDate, interestCalculatedFrom, currencyData);
|
||||
|
||||
// verification (post assertions)
|
||||
given(schedule).assertHasInstallmentSizeOf(4);
|
||||
given(schedule).assertTotalPaymentDueOf(1, is("57718.30")).assertInterestDueComponentOf(1, is("12000.00")).assertPrincipalDueComponentOf(1, is("45718.30"));
|
||||
given(schedule).assertTotalPaymentDueOf(2, is("57718.30")).assertInterestDueComponentOf(2, is("9256.90")).assertPrincipalDueComponentOf(2, is("48461.40"));
|
||||
given(schedule).assertTotalPaymentDueOf(3, is("57718.30")).assertInterestDueComponentOf(3, is("6349.22")).assertPrincipalDueComponentOf(3, is("51369.08"));
|
||||
given(schedule).assertTotalPaymentDueOf(4, is("57718.30")).assertInterestDueComponentOf(4, is("3267.08")).assertPrincipalDueComponentOf(4, is("54451.22"));
|
||||
}
|
||||
|
||||
private LoanScheduleAssertionBuilder given(final LoanSchedule schedule) {
|
||||
return new LoanScheduleAssertionBuilder(schedule);
|
||||
}
|
||||
|
||||
private class LoanScheduleAssertionBuilder {
|
||||
|
||||
private final LoanSchedule schedule;
|
||||
|
||||
public LoanScheduleAssertionBuilder(final LoanSchedule schedule) {
|
||||
this.schedule = schedule;
|
||||
}
|
||||
|
||||
public LoanScheduleAssertionBuilder assertPrincipalDueComponentOf(final int installmentNumber, Matcher<String> matchesExpectedAmount) {
|
||||
final Integer installmentIndex = installmentNumber -1;
|
||||
List<ScheduledLoanInstallment> repaymentInstallments = schedule.getScheduledLoanInstallments();
|
||||
ScheduledLoanInstallment repaymentInstallment = repaymentInstallments.get(installmentIndex);
|
||||
|
||||
assertThat("Expected principal due component for installment " + installmentNumber + " is wrong: ",
|
||||
repaymentInstallment.getPrincipalDue().toString(), matchesExpectedAmount);
|
||||
return this;
|
||||
}
|
||||
|
||||
public LoanScheduleAssertionBuilder assertInterestDueComponentOf(final int installmentNumber, Matcher<String> matchesExpectedAmount) {
|
||||
final Integer installmentIndex = installmentNumber -1;
|
||||
List<ScheduledLoanInstallment> repaymentInstallments = schedule.getScheduledLoanInstallments();
|
||||
ScheduledLoanInstallment repaymentInstallment = repaymentInstallments.get(installmentIndex);
|
||||
|
||||
assertThat("Expected interest due component for installment " + installmentNumber + " is wrong: ",
|
||||
repaymentInstallment.getInterestDue().toString(), matchesExpectedAmount);
|
||||
return this;
|
||||
}
|
||||
|
||||
public LoanScheduleAssertionBuilder assertTotalPaymentDueOf(final int installmentNumber, Matcher<String> matchesExpectedAmount) {
|
||||
final Integer installmentIndex = installmentNumber -1;
|
||||
List<ScheduledLoanInstallment> repaymentInstallments = schedule.getScheduledLoanInstallments();
|
||||
ScheduledLoanInstallment repaymentInstallment = repaymentInstallments.get(installmentIndex);
|
||||
|
||||
assertThat("Expected total payment for installment " + installmentNumber + " is wrong: ",
|
||||
repaymentInstallment.getTotalInstallmentDue().toString(), matchesExpectedAmount);
|
||||
return this;
|
||||
}
|
||||
|
||||
public LoanScheduleAssertionBuilder assertHasInstallmentSizeOf(int expectedInstallmentSize) {
|
||||
assertThat("Expected number of installments is wrong: ", schedule.getScheduledLoanInstallments().size(), is(expectedInstallmentSize));
|
||||
return this;
|
||||
}
|
||||
}
|
||||
}
|
||||
+41
@@ -0,0 +1,41 @@
|
||||
package org.mifosng.platform.loanschedule.domain;
|
||||
|
||||
import java.math.BigDecimal;
|
||||
|
||||
import org.mifosng.platform.currency.domain.MonetaryCurrency;
|
||||
import org.mifosng.platform.loan.domain.AmortizationMethod;
|
||||
import org.mifosng.platform.loan.domain.InterestCalculationPeriodMethod;
|
||||
import org.mifosng.platform.loan.domain.InterestMethod;
|
||||
import org.mifosng.platform.loan.domain.LoanProductRelatedDetail;
|
||||
import org.mifosng.platform.loan.domain.MonetaryCurrencyBuilder;
|
||||
import org.mifosng.platform.loan.domain.PeriodFrequencyType;
|
||||
|
||||
/**
|
||||
* This class is used to keep in one place configurations for setting up {@link LoanProductRelatedDetail} object used in {@link LoanScheduleGenerator}'s
|
||||
*/
|
||||
public class LoanProductRelatedDetailTestHelper {
|
||||
|
||||
public static LoanProductRelatedDetail createSettingsForEqualInstallmentAmortizationQuarterly() {
|
||||
MonetaryCurrency currency = new MonetaryCurrencyBuilder().withCode("USD").withDigitsAfterDecimal(2).build();
|
||||
BigDecimal defaultPrincipal = BigDecimal.valueOf(Double.valueOf("200000"));
|
||||
|
||||
// 2% per month, 24% per year
|
||||
BigDecimal defaultNominalInterestRatePerPeriod = BigDecimal.valueOf(Double.valueOf("2"));
|
||||
PeriodFrequencyType interestPeriodFrequencyType = PeriodFrequencyType.MONTHS;
|
||||
BigDecimal defaultAnnualNominalInterestRate = BigDecimal.valueOf(Double.valueOf("24"));
|
||||
|
||||
InterestMethod interestMethod = InterestMethod.DECLINING_BALANCE;
|
||||
InterestCalculationPeriodMethod interestCalculationPeriodMethod = InterestCalculationPeriodMethod.SAME_AS_REPAYMENT_PERIOD;
|
||||
Integer repayEvery = Integer.valueOf(3);
|
||||
PeriodFrequencyType repaymentFrequencyType = PeriodFrequencyType.MONTHS;
|
||||
|
||||
Integer defaultNumberOfRepayments = Integer.valueOf(4);
|
||||
AmortizationMethod amortizationMethod = AmortizationMethod.EQUAL_INSTALLMENTS;
|
||||
|
||||
BigDecimal inArrearsTolerance = BigDecimal.ZERO;
|
||||
|
||||
return new LoanProductRelatedDetail(currency, defaultPrincipal, defaultNominalInterestRatePerPeriod,
|
||||
interestPeriodFrequencyType, defaultAnnualNominalInterestRate, interestMethod,
|
||||
interestCalculationPeriodMethod, repayEvery, repaymentFrequencyType, defaultNumberOfRepayments, amortizationMethod, inArrearsTolerance);
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user