@Test
public void testGetActualPaymentWithNullRegularPayment() {
AmortizationAttributes amAttrs = generateAmortizationAttributesObjectTemplate();
amAttrs.setRegularPayment(null);
MonetaryAmount periodicPayment = AmortizationCalculator.getPeriodicPayment(amAttrs);
assertNotNull("Regular payment computed when initialized as null", periodicPayment);
}
@Test
public void testGetPaymentsAmortizedFully() {
AmortizationAttributes amAttrs = generateAmortizationAttributesObjectTemplate();
MonetaryAmount loanAmount = ofUSD(10000);
amAttrs.setLoanAmount(loanAmount);
amAttrs.setInterestRateAsPercent(7.);
amAttrs.setInterestOnly(false);
amAttrs.setPaymentFrequency(TimePeriod.Monthly.getPeriodsPerYear());
int termInMonths = 12;
amAttrs.setTermInMonths(termInMonths);
amAttrs.setAmortizationPeriodInMonths(12);
amAttrs.setCompoundingPeriodsPerYear(2);
amAttrs.setRegularPayment(AmortizationCalculator.getPeriodicPayment(amAttrs));
List<ScheduledPayment> schedule = AmortizationCalculator.generateSchedule(amAttrs);
MonetaryAmount interestTotal =
schedule.stream().map(payment -> payment.getInterest()).reduce((a, b) -> a.add(b)).get();
assertEquals("Amortized Interest total", ofUSD(377.67), interestTotal);
MonetaryAmount principalTotal =
schedule.stream().map(payment -> payment.getPrincipal()).reduce((a, b) -> a.add(b)).get();
assertEquals("Amortized Principal fully paid", loanAmount, principalTotal);
}
@Test
public void testGetPaymentsAmortizedWithOverPayment() {
AmortizationAttributes amAttrs = generateAmortizationAttributesObjectTemplate();
amAttrs.setLoanAmount(ofUSD(10000));
amAttrs.setInterestRateAsPercent(3.);
amAttrs.setInterestOnly(false);
amAttrs.setRegularPayment(ofUSD(400));
amAttrs.setPaymentFrequency(TimePeriod.SemiMonthly.getPeriodsPerYear());
int termInMonths = 24;
amAttrs.setTermInMonths(termInMonths);
amAttrs.setAmortizationPeriodInMonths(24);
amAttrs.setCompoundingPeriodsPerYear(2);
List<ScheduledPayment> schedule = AmortizationCalculator.generateSchedule(amAttrs);
assertEquals(
"Amortized payment count",
amAttrs.getPaymentFrequency() * termInMonths / 12,
schedule.size());
MonetaryAmount interestTotal =
schedule.stream().map(payment -> payment.getInterest()).reduce((a, b) -> a.add(b)).get();
assertEquals("Amortized Interest total", ofUSD(164.81), interestTotal);
}
@Test
public void testGenerateScheduleInterestOnlyMonthly() {
AmortizationAttributes amAttrs = generateAmortizationAttributesObjectTemplate();
amAttrs.setLoanAmount(ofUSD(10000));
amAttrs.setInterestRateAsPercent(10.);
amAttrs.setInterestOnly(true);
amAttrs.setPaymentFrequency(TimePeriod.Monthly.getPeriodsPerYear());
int termInMonths = 12;
amAttrs.setTermInMonths(termInMonths);
amAttrs.setAdjustmentDate(LocalDate.of(2016, Month.JANUARY, 1));
amAttrs.setRegularPayment(ofUSD(0));
List<ScheduledPayment> schedule = AmortizationCalculator.generateSchedule(amAttrs);
assertEquals("Interest only schedule term in months", termInMonths, schedule.size());
MonetaryAmount expectedInterest = ofUSD(83.34);
MonetaryAmount expectedPrincipal = ofUSD(0);
LocalDate expectedDate = amAttrs.getAdjustmentDate();
int index = 0;
for (ScheduledPayment payment : schedule) {
expectedDate = expectedDate.plusMonths(1L);
assertEquals("Interest only schedule payment number", ++index, payment.getPaymentNumber());
assertEquals("Interest only schedule payment date", expectedDate, payment.getPaymentDate());
assertEquals(
"Interest only schedule payment interest", expectedInterest, payment.getInterest());
assertEquals(
"Interest only schedule payment principal", expectedPrincipal, payment.getPrincipal());
assertEquals(
"Interest only schedule payment total payment", expectedInterest, payment.getPayment());
assertEquals(
"Interest only schedule payment loan principal", ofUSD(10000), payment.getBalance());
}
}
private AmortizationAttributes generateAmortizationAttributesObjectTemplate() {
AmortizationAttributes amAttrs = new AmortizationAttributes();
amAttrs.setLoanAmount(USD50000);
amAttrs.setRegularPayment(USD50000.divide(100));
amAttrs.setStartDate(LocalDate.of(2015, Month.DECEMBER, 28));
amAttrs.setAdjustmentDate(LocalDate.of(2016, Month.JANUARY, 1));
amAttrs.setTermInMonths(24);
amAttrs.setInterestOnly(false);
amAttrs.setAmortizationPeriodInMonths(300);
amAttrs.setCompoundingPeriodsPerYear(2);
amAttrs.setPaymentFrequency(12);
amAttrs.setInterestRateAsPercent(12.);
return amAttrs;
}