update:demo13

com/study/demo13/PaymentService.java

@@ -0,0 +1,77 @@
+package com.study.demo13;
+
+interface Payable {
+    boolean pay(double amount);
+    String getPayType();
+}
+
+abstract class Account implements Payable {
+    protected double balance;
+
+    public Account(double balance) {
+        this.balance = balance;
+    }
+
+    protected boolean canPay(double total) {
+        return balance >= total;
+    }
+
+    public double getBalance() {
+        return balance;
+    }
+}
+
+class BankAccount extends Account {
+    public BankAccount(double balance) {
+        super(balance);
+    }
+
+    @Override
+    public boolean pay(double amount) {
+        if (canPay(amount)) {
+            balance -= amount;
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public String getPayType() {
+        return "BANK";
+    }
+}
+
+class WalletAccount extends Account {
+    public WalletAccount(double balance) {
+        super(balance);
+    }
+
+    @Override
+    public boolean pay(double amount) {
+        double total = amount * 1.05;
+        if (canPay(total)) {
+            balance -= total;
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public String getPayType() {
+        return "WALLET";
+    }
+}
+
+public class PaymentService {
+    public static void main(String[] args) {
+        Payable bank = new BankAccount(1000.0);
+        Payable wallet = new WalletAccount(500.0);
+        Payable bank2 = new BankAccount(100.0);
+        Payable wallet2 = new WalletAccount(50.0);
+
+        System.out.println("支付方式: " + bank.getPayType() + ", 支付 200: " + (bank.pay(200) ? "成功" : "失败") + ", 余额: " + ((BankAccount) bank).getBalance());
+        System.out.println("支付方式: " + wallet.getPayType() + ", 支付 100: " + (wallet.pay(100) ? "成功" : "失败") + ", 余额: " + String.format("%.2f", ((WalletAccount) wallet).getBalance()));
+        System.out.println("支付方式: " + bank.getPayType() + ", 支付 200: " + (bank2.pay(200) ? "成功" : "失败") + ", 余额: " + ((BankAccount) bank2).getBalance());
+        System.out.println("支付方式: " + wallet.getPayType() + ", 支付 100: " + (wallet2.pay(100) ? "成功" : "失败") + ", 余额: " + String.format("%.2f", ((WalletAccount) wallet2).getBalance()));
+    }
+}