Java面向对象多态性设计account账户类

Question

Answer 1

看看这个是不是你想要的。

public class Account {

    // id
    private int id = 0;

    // balance
    private double balance = 0;

    // 年利率
    private double annualInterestRate = 0;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public double getBalance() {
        return balance;
    }

    public void setBalance(double balance) {
        this.balance = balance;
    }

    public double getannualInterestRate() {
        return annualInterestRate;
    }

    public void setannualInterestRate(double annualInterest) {
        this.annualInterestRate = annualInterest;
    }

    // 无参构造方法
    public Account() {}

    // id和初始余额的构造方法
    public Account(int id, double balance) {
        this.id = id;
        this.balance = balance;
    }

    // 返回月利率方法
    public double getMonthlyInterestRate(){
        return this.annualInterestRate / 12;
    }

    // 取款方法
    public void withDraw(double num){
        if(num > balance){
            System.out.println("金额不足，请修改金额");
            return;
        }
        this.balance = this.balance - num;
    }

    // 存款方法
    public void deposit(double num){
        if(num < 0){
            System.out.println("输入金额错误，请重新输入金额");
            return;
        }
        this.balance = this.balance + num;
    }

    public static void main(String[] args) {
        Account account = new Account(1122, 2000);
        account.setannualInterestRate(0.045);
        // 取款2500
        account.withDraw(2500);
        // 存款3000
        account.deposit(3000);
        System.out.println("月利率：" + account.getMonthlyInterestRate() + "，余额：" + account.getBalance());
        // 再取款25000
        account.withDraw(25000);
    }
}