檔案文件的操作在開發過程中很經常要用到。Java中封裝了許多非常有用的檔案操作API，非常方便。下面我就展示Java簡單讀寫文字文件（txt檔案）的示例程式碼。

環境

JDK1.8

示例程式碼

import java.io.*;
import java.util.ArrayList;
import java.util.List;

/**
 * @author huangh
 * @date 2018-08-19 8:35
 * @desc 文字文件的讀和寫
 */
public class TxtManage {

    /**
     * 讀取指定路徑的文字文件
     *
     * @param
 
 filePath
     * @return
     */
    public static List<String> readTxt(String filePath) {

        File txtFile = new File(filePath);
        List<String> txtContent = new ArrayList<>();

        try {
            InputStream in = new FileInputStream(txtFile);
            //編碼可設定為GBK，UTF-8等
 

            BufferedReader reader = new BufferedReader(new InputStreamReader(in, "GBK"));

            //reader.readLine()讀入每一行的內容
            String line = reader.readLine();

            //line為null表示讀完
            while (line != null) {
                txtContent.add(line);
                //讀取下一行
                line = reader.readLine();
            }

        } catch
 
 (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        //返回讀取的結果
        return txtContent;

    }

    /**
     * 寫入指定路徑文字文件
     *
     * @param filePath
     */
    public static void writeTxt(String filePath) {

        File file = new File(filePath);
        try {
            BufferedWriter writer = new BufferedWriter(new FileWriter(file));

            String data;

            data = "業精於勤荒於嬉";
            //寫入文字文件
            writer.write(data);
            //換行
            writer.write("\r\n");

            data = "行成於思毀於隨";
            writer.write(data);
            writer.write("\r\n");

            data = "不積跬步，無以至千里";
            writer.write(data);
            writer.write("\r\n");

            writer.flush();
            writer.close();


        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    public static void main(String[] args) {

        //讀文字文件
        List<String> txtContent = readTxt("D:\\Data\\testRead.txt");
        txtContent.forEach(System.out::println);

        //寫文字文件
        writeTxt("D:\\Data\\testWrite.txt");
    }

}