Java讀寫文本文件

1.需求

以UTF-8編碼，讀寫txt文件。

2.代碼

2.1.寫文件

        File file = new File("d://textfile.txt");
        FileOutputStream fileOutputStream = new FileOutputStream(file);
        BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(fileOutputStream, "UTF-8"));
        writer.write("hello world\n");
        writer.write("yep?");
        writer.flush();
        fileOutputStream.close();
        writer.close();

剛開始是直接使用FileWriter來寫入，如下：

File file = new File("d:\\textfile.txt");
FileWriter fieWriter = new FileWriter(file);
fileWriter.write("helllo word\n");
fileWriter.write("yep?");
fieWriter.flush();
fileWriter.close();

但是這樣沒辦法指定編碼，中文可能會遇到亂碼現象。因此，只有將File先加入FileOutputStream，然後new OutputStreamWriter的時候指定編碼。

2.2.讀文件

        File file = new File("d://textfile.txt");
        FileInputStream fileInputStream = new FileInputStream(file);
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(fileInputStream, "UTF-8"));
        String str = "";
        while ((str = bufferedReader.readLine()) != null) {
            System.out.println(str);
        }

        fileInputStream.close();
        bufferedReader.close();

3.Tips

文件讀寫，無非是Writer、Reader，以及讀取File到流裏面。以及Buffer。