如何为未定义的方法解决此错误？答案

【问题标题】：How do I solve this error for an undefined method?如何为未定义的方法解决此错误？
【发布时间】：2013-10-31 23:58:43
【问题描述】：

这就是我正在使用的。这是一个月供贷款计算器。我不断收到错误消息“方法monthlyPayment (double, int, int) 未定义类型Assignment 8。”此错误显示在 main 方法中。错误在第 27 行。

类

public class LoanCalc {
public static double monthlyPayment(double amountBorrowed, int loanLength, int intRate) {
        double principal;
        double interestRate;
        double monthlyPayment;

        principal = amountBorrowed;
        interestRate = intRate / 100 / 12;

        monthlyPayment = (interestRate * principal) /
                (1- Math.pow((1 + interestRate) , - loanLength * 12 ));



        return monthlyPayment;
    }
}

主要方法

1    import java.util.Scanner;
2    
3    public class Assignment8 {
4    
5       public static void main(String[] args) {
6           
7           Scanner kbd = new Scanner(System.in);
8           
9           System.out.println("Enter the amount borrowed: ");
10          double amountBorrowed = kbd.nextDouble();
11          
12          System.out.println("Enter the interest rate: ");
13          int intRate = kbd.nextInt();
14          
15          System.out.println("Enter the minimum length of loan: ");
16          int minLength = kbd.nextInt();
17          
18          System.out.println("Enter the maximum length of loan: ");
19          int loanLength = kbd.nextInt();
20          while (loanLength < minLength) {
21              System.out.println("Invalid input: Input must be greater than      22                       minimum length of loan");
23              System.out.println("Enter the maximum length of loan: ");
24              loanLength = kbd.nextInt();
25          }
26          
27          double payment = monthlyPayment(amountBorrowed, loanLength, intRate);
28          System.out.println(payment);
29          
30      }

    }

【问题讨论】：

标签： java

【解决方案1】：

改成

double payment = LoanCalc.monthlyPayment(amountBorrowed, loanLength, intRate);

这是因为monthlyPayment()属于LoanCalc，而不是Assignment8，所以需要明确说明在哪里可以找到monthlyPayment()。

【讨论】：

【解决方案2】：

你必须调用函数使用

LoanCalc.monthlyPayment( ... )

因为它是属于另一个类的静态方法。

【讨论】：