Bank3

package banking3;

//账户
public class Account {
    private double balance;// 账户余额

    public Account(double init_balance) {
        balance = init_balance;
    }

    public double getBlance() {
        return balance;
    }

    // 存钱
    public boolean deposit(double amt) {// amt 要存的额度
        balance += amt;
        return true;
    }

    // 取钱
    public boolean withdraw(double amt) {// amt：要取得额度
        if (balance >= amt) {
            balance -= amt;
            return true;
        } else {
            System.out.println("余额不足");
            return false;
        }
    }
}

package banking3;
public class Customer {
    private String firstName;
    private String lastName;
    private Account account;

    public Customer(String f, String l) {
        firstName = f;
        lastName = l;
    }

    public String getFirstName() {
        return firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public Account getAccount() {
        return account;
    }

    public void setAccount(Account acct) {
        account = acct;
    }
}

package TestBanking;

import banking3.Account;
import banking3.Customer;

public class TestBanking3 {
    public static void main(String[] args) {
        Customer customer;
        Account account;

        // Create an account that can has a 500.00 balance.
        customer = new Customer("Jane", "Smith.");
        account = new Account(500.00);

        System.out.println("Creating the customer Jane Smith.");
        // code
        customer.setAccount(account);

        System.out.println("Creating her account with a 500.00 balance.");

        // code
        // Perform some account transactions
        System.out.println("Withdraw 150.00: " + account.withdraw(150.00));
        System.out.println("Deposit 22.50: " + account.deposit(22.50));
        System.out.println("Withdraw 47.62: " + account.withdraw(47.62));
        System.out.println("Withdraw 400.00: " + account.withdraw(400.00));

        // Print out the final account balance
        System.out.println("Customer [" + customer.getLastName() + ", " 
+ customer.getFirstName()+ "] has a balance of " + account.getBlance());
    }
}


输出结果：

Withdraw 47.62: true
余额不足
Withdraw 400.00: false
Customer [Smith., Jane] has a balance of 324.88