computemortgage.java

此源码为机械工业出版社出版的《Java语言程序设计》第三版所配套的书中所有源代码。

// ComputeMortgage.java: Compute mortgage payments
public class ComputeMortgage
{
  // Main method
  public static void main(String[] args)
  {
    double annualInterestRate;
    int numOfYears;
    double loanAmount;

    // Enter monthly interest rate
    System.out.println(
      "Enter yearly interest rate, for example 8.25: ");
    annualInterestRate = MyInput.readDouble();

    // Obtain monthly interest rate
    double monthlyInterestRate = annualInterestRate/1200;

    // Enter number of years
    System.out.println(
      "Enter number of years as an integer, for example 5: ");
    numOfYears = MyInput.readInt();

    // Enter loan amount
    System.out.println("Enter loan amount, for example 120000.95: ");
    loanAmount = MyInput.readDouble();

    // Calculate payment
    double monthlyPayment = loanAmount*monthlyInterestRate/
      (1 - 1/(Math.pow(1 + monthlyInterestRate, numOfYears*12)));
    double totalPayment = monthlyPayment*numOfYears*12;

    // Display results
    System.out.println("The monthly payment is " + monthlyPayment);
    System.out.println("The total payment is " + totalPayment);
  }
}