Java 使用继承来计算定期存款和定期储蓄的利息

继承是一种允许我们访问一个类的属性和行为的概念，让另一个类可以继承这些方法和成员变量。被继承的类称为超类或父类，继承这些方法和成员变量的类称为子类或子类。在Java中，我们使用“extends”关键字来继承一个类。

在本文中，我们将讨论一个Java程序，使用继承来计算定期存款和定期储蓄的利息。首先，在您的本地机器IDE中创建这四个Java文件：

Acnt.java - 这个文件将包含一个抽象类“Acnt”，用于存储账户详细信息，如利率和金额。它还将具有一个带有参数“amnt”用于计算利率的抽象方法“calcIntrst”。
FDacnt.java - 它将计算定期存款的利率。在它里面，“FDacnt”类将继承“Acnt”类并重写“calcIntrst”方法。
RDacnt.java - 它将计算定期储蓄的利率。在它里面，“RDacnt”类将继承“Acnt”类并重写“calcIntrst”方法。
Intrst.java - 这个文件将包含主方法。

示例

Acnt.java

public abstract class Acnt{
    double intrstRate;
    double amnt; 
    abstract double calcIntrst(double amnt);
}

FDacnt.java

import java.util.*;
public class FDacnt extends Acnt {
   double FDintrstRate;
   double FDAmnt;
   int period;
   int age;
   double Gen, SenCitizen;
   Scanner input = new Scanner(System.in);
   @Override
   double calcIntrst(double amnt){
      this.FDAmnt = amnt;
      System.out.println("Enter your FD days");
      period = input.nextInt();
      System.out.println("Enter the age of account holder ");
      age = input.nextInt();
      if (amnt < 10000000) {
         if (period >= 7 && period <= 14) {
            Gen = 0.0450;
            SenCitizen = 0.0500;
         } else if (period >= 15 && period <= 29) {
            Gen = 0.0470;
            SenCitizen = 0.0525;
         } else if (period >= 30 && period <= 45) {
            Gen = 0.0550;
            SenCitizen = 0.0600;
         } else if (period >= 45 && period <= 60) {
            Gen = 0.0700;
            SenCitizen = 0.0750;
         } else if (period >= 61 && period <= 184) {
            Gen = 0.0750;
            SenCitizen = 0.0800;
         } else if (period >= 185 && period <= 365) {
            Gen = 0.0800;
            SenCitizen = 0.0850;
         }
         FDintrstRate = (age < 50) ? Gen : SenCitizen;
      } else {
         if (period >= 7 && period <= 14) {
            intrstRate = 0.065;
         } else if (period >= 15 && period <= 29) {
            intrstRate = 0.0675;
         } else if (period >= 30 && period <= 45) {
            intrstRate = 0.00675;
         } else if (period >= 45 && period <= 60) {
            intrstRate = 0.080;
         } else if (period >= 61 && period <= 184) {
            intrstRate = 0.0850;
         } else if (period >= 185 && period <= 365) {
            intrstRate = 0.10;
         }
      }
      return FDAmnt * FDintrstRate;
   }
}

RDacnt.java

import java.util.*;
public class RDacnt extends Acnt{
   double RDIntrstRate;
   double RDamnt;
   int periods;
   double monthlyAmnt;
   double Gen, SenCitizen;
   Scanner input = new Scanner(System.in);
   @Override
   double calcIntrst(double amnt){
      this.RDamnt = amnt;
      System.out.println("Enter your RD months");
      periods =input.nextInt();
      System.out.println("Enter the age of account holder");
      int age =input.nextInt();
      if (periods >= 0 && periods <= 6) {
         Gen = .0750;
         SenCitizen = 0.080;
      } else if (periods >= 7 && periods <= 9) {
         Gen = .0775;
         SenCitizen = 0.0825;
      } else if (periods >= 10 && periods <= 12) {
         Gen = .0800;
         SenCitizen = 0.0850;
      } else if (periods >= 13 && periods <= 15) {
         Gen = .0825;
         SenCitizen = 0.0875;
      } else if (periods >= 16 && periods <= 18) {
         Gen = .0850;
         SenCitizen = 0.0900;
      } else if (periods >= 22) {
         Gen = .0875;
         SenCitizen = 0.0925;
      }
      RDIntrstRate = (age < 50) ? Gen : SenCitizen;
      return RDamnt * RDIntrstRate;
   }
}

Intrst.java

import java.util.*;
public class Intrst{
   public static void main(String[] args){
      Scanner sc = new Scanner(System.in);
      System.out.println("Choose from the Options: " + "\n1." + " FD Interest" + " \n2." + " RD Interest"
      + "\n3." + " Exit");
      int choice = sc.nextInt();
      switch (choice){
         case 1:
         FDacnt fds = new FDacnt();
         System.out.println("Enter your FD Amount");
         double fAmnt = sc.nextDouble();
         System.out.println("Interest gained on your FD Amount is:  $" + fds.calcIntrst(fAmnt)); break; case 2: RDacnt rds = new RDacnt(); System.out.println("Enter your RD amount"); double RAmnt = sc.nextDouble(); System.out.println("Interest gained on your RD Amount is:$  " + rds.calcIntrst(RAmnt));
         break;
         default:
         System.out.println("Choose correct choice");
      }
   }
}

要编译此代码，请键入以下命令：javac Intrst.java 现在运行：java Intrst

输出

Choose from the Options: 
1. FD Interest
2. RD Interest
3. Exit
1
Enter your FD Amount
56000
Enter your FD days
325
Enter the age of account holder 
32
Interest gained on your FD Amount is: $ 4480.0

上面的程序是一个菜单驱动程序。当我们执行这个程序时，屏幕上会显示三个选项。选择1来计算定期存款的利率，选择2来计算定存的利率。