Java 開発: 単体テストと統合テストを行う方法

public class Calculator {
    public int add(int a, int b) {
        return a + b;
    }
}

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

public class CalculatorTest {
    Calculator calculator = new Calculator();

    @Test
    public void testAdd() {
        int result = calculator.add(2, 3);
        Assertions.assertEquals(5, result);
    }
}

public class PaymentService {
    public boolean makePayment(double amount) {
        // 实际的支付逻辑
        if (amount > 0) {
            // 支付成功
            return true;
        } else {
            // 支付失败
            return false;
        }
    }
}

public class EmailService {
    public void sendEmail(String email, String message) {
        // 实际的发送邮件逻辑
    }
}

public class OrderService {
    private PaymentService paymentService;
    private EmailService emailService;

    public OrderService(PaymentService paymentService, EmailService emailService) {
        this.paymentService = paymentService;
        this.emailService = emailService;
    }

    public boolean processOrder(double amount, String email) {
        boolean paymentStatus = paymentService.makePayment(amount);
        if (paymentStatus) {
            emailService.sendEmail(email, "Your order has been processed successfully.");
            return true;
        } else {
            emailService.sendEmail(email, "Payment failed. Please try again.");
            return false;
        }
    }
}

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

public class OrderServiceTest {
    @Test
    public void testProcessOrder() {
        PaymentService paymentService = new PaymentService();
        EmailService emailService = new EmailService();
        OrderService orderService = new OrderService(paymentService, emailService);
        
        boolean result = orderService.processOrder(100.0, "example@example.com");
        
        Assertions.assertTrue(result);
    }
}