Question

我正在创建一个程序，该程序的机队具有诸如载重量和重量限制之类的规格。有需要进入飞机的物品的货物清单。我有货运课，飞机课和主装载机课。我想让飞机上放一堆货物。我觉得我已经很接近完成这项工作，但是我可能会缺少一些东西。我在将getter和setter的语法与push和pop结合使用时遇到麻烦。

package sandbox;

import java.util.Stack;

public class StacksMain {

    public static void main(String[] args) {
        Airplane aircraft = new Airplane();
        Cargo exampleLoad = new Cargo(1, 2, 3, 4);
        Cargo exampleLoad2 = new Cargo(1, 5, 3, 4);
        // test stack
        Stack<Cargo> testStack = new Stack<Cargo>();
        // set cargo in current aircraft
        aircraft.setCurrentCargo(testStack);
        // push new cargo into aircraft
//this is where i'm running into the issue
        aircraft.setCurrentCargo().push(exampleLoad2);

        testStack.push(exampleLoad);
        System.out.println(testStack.pop().getValue());

    }

}

package sandbox;    

    public class Cargo {
        private int trackingNum;
        private int cubicFeet;
        private int value; 
        private int weight;

        public Cargo(int trackingNum, int cubicFeet, int value, int weight) {
            setTrackingNum(trackingNum);
            setCubicFeet(cubicFeet);
            setValue(value);
            setWeight(weight);
}

        public int getWeight() {
            return weight;
        }

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

        public int getTrackingNum() {
            return trackingNum;
        }

        public void setTrackingNum(int trackingNum) {
            this.trackingNum = trackingNum;
        }

        public int getCubicFeet() {
            return cubicFeet;
        }

        public void setCubicFeet(int cubicFeet) {
            this.cubicFeet = cubicFeet;
        }

        public int getValue() {
            return value;
        }

        public void setValue(int value) {
            this.value = value;
        }
}

package sandbox;

import java.util.Stack;

public class Airplane {
    private Stack<Cargo> currentCargo;

    public Airplane() {
        setCurrentCargo(currentCargo);


    }

    public Stack<Cargo> getCurrentCargo() {
        return currentCargo;
    }

    public void setCurrentCargo(Stack<Cargo> currentCargo) {
        this.currentCargo = currentCargo;
    }
}

Answer 1

您的setCurrentCargo()方法是void，因此您无法在该方法的结果上调用push。您也不需要；这个

aircraft.setCurrentCargo(testStack);
// push new cargo into aircraft
//this is where i'm running into the issue
aircraft.setCurrentCargo().push(exampleLoad2);

可能是

aircraft.setCurrentCargo(testStack);
// push new cargo into aircraft
aircraft.getCurrentCargo().push(exampleLoad2);

但是，因为您只是将货物设置为testStack，所以我希望

aircraft.setCurrentCargo(testStack);
// push new cargo into aircraft
testStack.push(exampleLoad2);

Answer 2

您好，您只需将aircraft.setCurrentCargo().push(exampleLoad2);替换为aircraft.getCurrentCargo().push(exampleLoad2);。

推入并弹出对象内部的堆栈

2 个答案: