读文件
public static String[] readFilePram(String filename) throws IOException {
    FileReader fr = new FileReader(filename);
    BufferedReader br = new BufferedReader(fr);
    String line;
    String[] args = null;
    while ((line = br.readLine()) != null) {
        args = line.split(",");
    }
    br.close();
    fr.close();
    return args;
}

写文件

publi static void writeFilePram(String dir, String filename, String content) throws IOException {
    File file = new File(dir + filename);

    FileOutputStream fw = null;
    if (!file.exists()) {
        file.createNewFile();
        fw = new FileOutputStream(file);
    } else {
        fw = new FileOutputStream(file, true);
    }
    OutputStreamWriter bw = new OutputStreamWriter(fw, "UTF-8");

    bw.write( content + "\r\n");

    bw.close();
    fw.close();
}