java - 我的数组列表到 .txt 文件程序给了我几个错误

Question

我有一个库存应用程序，它根据用户输入设置字符串列表。比它应该将字符串导出到 .txt 文件。 我以前从未使用过 FileWriter，并且非常困惑。

感谢任何帮助。

这是所有相关代码:

靠近末尾的三行有“writer”。他们给了我一个unreported exception IOException; must be caught or declared to be thrown .

import java.util.*;
import java.io.FileWriter;

public class mVentory extends javax.swing.JFrame {

    /**
     * Creates new form mVentory
     */
    public mVentory() {
        initComponents();

    }

    public class ProductInfo {

        String name;
        String des;
        String ID;
        String num;

        public ProductInfo(String name, String des, String ID, String num) {
            this.name = name;
            this.des = des;
            this.ID = ID;
            this.num = num;
        }
    }

    public static void Inventory() {

    }

    //creat Array
    ArrayList<String> Inventory = new ArrayList<String>();

    private void AddGoActionPerformed(java.awt.event.ActionEvent evt) {
        // Add Item
        String Name, Description, Identification, Number, Item;

        Name = NameIn.getText();
        Description = DesIn.getText();
        Identification = IDIn.getText();
        Number = NumIn.getText();

        Item = "" + Name + "," + Description + "," + Identification + "," + Number + ".";

        Inventory.add(new String(Item));

        NameIn.setText("");
        DesIn.setText("");
        IDIn.setText("");
        NumIn.setText("");

    }

    private void ExportGoActionPerformed(java.awt.event.ActionEvent evt) {
        FileWriter writer;
        writer = new FileWriter("Inventory.txt");
        for (String str : Inventory) {
            writer.write(str);
        }
        writer.close();
    }
}

Answer 1

您的 writer 周围需要一个 try/catch 语句。

如:

private void ExportGoActionPerformed(java.awt.event.ActionEvent evt) {
    FileWriter writer = null;
    try {
        writer = new FileWriter("Inventory.txt");
        for (String str : Inventory) {
            writer.write(str);
        }
    } catch (IOException e) {
        //handle exception, rethrow or log
        e.printStackTrace();
    } finally {
        try {
            writer.close();
        } catch (IOException ignore){

        }
    }
 }