java - 未编译的基本Java程序

Question

我已经编写了以下代码，但是由于错误，未成功编译。请指教!该错误显示“错误:不兼容的类型:不能将double转换为 bool(boolean) 值”以及“错误:不兼容的类型: bool(boolean) 不能被转换为double值”。

class BMITest {
    public static void main(String[] args) {
        showData(fullName("John", "McDermott"), 178, 74.3);
}

    public static void showData(String name, double height, double weight) {
        double bmi = BMInum(height, weight);
        System.out.println("His name is " + name + ", and his BMI is " + bmi);

        if (isHealthy(bmi)) {
            System.out.println("He is healthy.");
        } else {
            System.out.println("He's not healthy.");
        }
    }

    public static String fullName(String first, String last) {
        return first + " " + last;
    }

    public static double BMInum(double height, double weight) {
        return weight / height / height * 10000;
    }

    public static double isHealthy(double bmi) {
        return bmi >= 18.5 && bmi < 25.0;
    }


}

Answer 1

将您的isHealthy方法更改为

public static boolean isHealthy(double bmi) {
    return bmi >= 18.5 && bmi < 25.0;
}