java - boolean if 语句

Question

public class Health
{
    boolean dependency;
    String insuranceOwner = "";
    static final int basicHealthFee = 250;
    static final int healthDiscount = 20;

    public Health(boolean dependent, String insurance)  
    {  
        dependency = dependent;  
        insuranceOwner = insurance;  
    }

    public double computeCost()
    {
        double healthFee;
        if (dependency == true)
        {
            healthFee = basicHealthFee - (basicHealthFee * (healthDiscount/100.0));
        }
        else 
        {
            healthFee = basicHealthFee;
        }

        return healthFee;
    }
}

 Health h34 = new Health(true, "Jim");         
 System.out.println("discount price: " + h34.computeCost());

当我输入 true 作为构造函数的参数时，我的 computeCost 方法仍然运行该 block ，就好像依赖项 == false 一样。有什么原因吗？

Answer 1

您正在成为整数除法的牺牲品。 20/100 == 0，任何乘以它的结果都是 0。要解决这个问题，请将您的 static final int 声明更改为 double。

static final double basicHealthFee = 250D;
static final double healthDiscount = 20D;

D 定义了一个 double literal .