java - 创建对象时如何修复 "Error: Cannot find symbol"？

Question

我不明白我的编译器如何找不到类 Weight，考虑到我不是已经在我的 public boolean checkWeight 方法中创建了它吗？编译器指向这一行:

`Weight first = new Weight();`

和

`Weight second = new Weight();`

<小时/>

public class Guard {

    int stashWeight;

    public Guard ( int maxWeight ) {
        this.stashWeight = maxWeight;
    }

    public boolean checkWeight (Weight maxWeight) {
        if ( maxWeight.weight >= stashWeight ) {
            return true;
        } else {
            return false;
        }
    }

    public static void main (String[] args ) {
        Weight first = new Weight();
        first.weight = 3000;
        Weight second = new Weight();
        second.weight = 120;

        Guard grams = new Guard(450);
        System.out.println("Officer, can I come in?");
        boolean canFirstManGo = grams.checkWeight(first);
        System.out.println(canFirstManGo);

        System.out.println();

        System.out.println("Officer, how about me?");
        boolean canSecondManGo = grams.checkWeight(second);
        System.out.println(canSecondManGo);

    }
}

Answer 1

您应该像这样定义Weight 类:

public class Weight {

    public int weight;

    public int getWeight() {
        return weight;
    }

    public void setWeight(int weight) {
        this.weight = weight;
    }
}

输出:

Officer, can I come in?
true

Officer, how about me?
false

或者使用 import 关键字导入您的 Weight 类。