Question

Item.java

我有一个变量名称和重量的项目

package com.company;

public class Item {
    String name;
    Double weight;
}

Bag.java

袋子最多可以容纳20公斤物品。

package com.company;

public class Bag {
    Item [] myBags;
    int itemCount;
    Double currentWeight;

    Bag(){
        itemCount = 0;
        currentWeight = 0.0;
        myBags = new Item[50];
    }
    boolean canAddItem(Item item) {
            if (currentWeight + item.weight > 20) {
                return false;
            } else {
                return true;
            }
        }

    void AddItem(Item item){
        myBags[itemCount] = item;
        currentWeight = currentWeight + myBags[itemCount].weight;
        itemCount++;
    }
}

Main.java

package com.company;

public class Main {

    public static void main(String[] args) {
    // write your code here

        Bag myBag = new Bag();

        /*item 1*/
        Item fishing_rod = new Item();
        fishing_rod.name = "rod1";
        fishing_rod.weight = 10.4;

        if(myBag.canAddItem(fishing_rod)){
        myBag.AddItem(fishing_rod);}



        /*item 2*/
        Item axe = new Item();
        axe.name = "axe1";
        axe.weight = 2.2;

        if(myBag.canAddItem(axe)){
            myBag.AddItem(axe);}


        System.out.println(myBag.currentWeight);
        //System.out.println(myBag.myBags); i want to show that's here

    }
}

我在袋子里增加了两个物体。我想展示我添加到书包中的所有对象。

如何显示？如何在Java中显示？

感谢您的帮助

Answer 1

您必须重写类中的toString()方法：对于首先 Item 类：

@Override
public String toString() {
    return "Name: "+ name + ": weight "+ weight +"Kg";
}

然后袋课

@Override
public String toString() {
    return Arrays.toString(myBags);
}

通过这种方式，每次打印包包时，您都会得到其中的内容。

Answer 2

在袋类中：

\/FJw==

在主要方法中： public void printBag() { for(int i =0; i< itemCount; i++) { System.out.println("Name: " + myBags[i].name); System.out.println("Weight: " + myBags[i].weight); } }

Answer 3

在Bag类中定义一个函数：

public void printBag() {
    for(Item element : myBags) {
       System.out.println('Name: ' + element.name);
       System.out.println('Weight: ' + element.weight);
    }
}

然后从main调用它：

myBag.printBag();

如何显示Java上的所有对象

3 个答案: