来自不同类的对象ArrayList

Question

Java新手。

我有一个txt文件：

• 帽子，20，1个
• 裤，50％，45轮
• 鞋，100，10

在一类被称为商品我有能够读取它，使用分隔符分割它，将它添加到一个ArrayList。

我有另一个名为GoodsList的类，我将创建一个ArrayList，它应该具有上述的对象，如果用户请求它可以使用它。谢谢

Answer 1

我想你是在问关于Java泛型。 如果是这样，请创建您的Goods类，因为您需要通过ArrayList将其作为对象进行访问。

public Class Goods implements Serializable { 
    private String goodName; 
    private double price; 
    private int quantity; 

    public String getGoodName() { 
    return goodName; 
    } 

    public void setGoodName(String goodName) { 
    this.goodName = goodName; 
    } 

    public double getPrice() { 
    return price; 
    } 

    public void setPrice(double price) { 
    this.price = price; 
    } 

    public int getQuantity() { 
    return quantity; 
    } 

    public void setQuantity(int quantity) { 
    this.quantity = quantity; 
    } 

} 

，然后写您的商品详细资料类创建列表与商品对象设置：

public class GoodsList { 

    public static void main(String args[]) { 

    Goods g = new Goods(); 
    Goods g2 = new Goods(); 
    Goods g3 = new Goods(); 

    g.setGoodName("hat"); 
    g.setQuantity(50); 
    g.setPrice(100.00); 

    g2.setGoodName("pants"); 
    g2.setQuantity(50); 
    g2.setPrice(100.00); 

    g3.setGoodName("shoes"); 
    g3.setQuantity(50); 
    g3.setPrice(100.00); 

    List <Goods> goodsList = new ArrayList <Goods>(); 
    goodsList.add(g); 
    goodsList.add(g2); 
    goodsList.add(g3); 


    //printing goods: 

    for (Goods g: goodsList) { 
     System.out.println(g.getGoodName() + "," + g.getQuantity() + "," + g.getPrice()); 
    } 

    } 

} 

的是，你在找什么？

Answer 2

你是否在寻找类似：

public class FileReaderExample 
{ 


    public class Goods 
    { 

    private String goodName = null; 
    private String price = null; 
    private String quantity = null; 

    public Goods(String goodName ,String price,String quantity) 
    { 
     this.goodName = goodName; 
     this.price = price; 
     this.quantity = quantity; 
    } 

    public String getGoodName() 
    { 
     return goodName; 
    } 

    public void setGoodName(String goodName) 
    { 
     this.goodName = goodName; 
    } 

    public String getPrice() 
    { 
     return price; 
    } 

    public void setPrice(String price) 
    { 
     this.price = price; 
    } 

    public String getQuantity() 
    { 
     return quantity; 
    } 

    public void setQuantity(String quantity) 
    { 
     this.quantity = quantity; 
    } 
    } 

    private ArrayList<Goods> populateGoods() 
    { 
    ArrayList<Goods> goodsList = new ArrayList<Goods>(); 

    File file = new File("d:\\text.txt"); 
    try 
    { 
     BufferedReader br = new BufferedReader(new FileReader(file)); 
     String line; 
     while ((line = br.readLine()) != null) 
     { 

      String[] itemsOnLine = line.trim().split(","); 
      goodsList.add(new Goods(itemsOnLine[0],itemsOnLine[1],itemsOnLine[2])); 
     } 
    } 
    catch (IOException e) 
    { 
     e.printStackTrace(); 
    } 
    return goodsList; 
    } 


    public static void main(String[] args) 
    { 
    FileReaderExample fileReaderExample = new FileReaderExample(); 
    ArrayList<Goods> goodsList = fileReaderExample.populateGoods(); 

    for (Goods goods : goodsList) 
    { 
     System.out.println(goods.getGoodName()); 
    } 
} 
}