java 文件续写

public class FileWriterDemo {
    public static void main(String[] args) {
        FileWriter fw = null;
        try {
            // 传递true，代表不覆盖已有文件，追加
            fw = new FileWriter("demo.txt", true);
            fw.write("abcde\n");
        } catch (IOException e) {
            System.out.println(e.toString());
        } finally {
            try {
                if (fw != null)
                    fw.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}