Android【File文件存储工具类】

最近写项目用到了文件存储，当需要频繁的存储操作的时候，文件存储性能方面远大于SharedPreferences 。

工具类复制可用

public class FileUtils {

    // 将字符串写入到文本文件中
    public static void writeTxtToFile(String strcontent, String filePath, String fileName) {
        //生成文件夹之后，再生成文件，不然会出错
        makeFilePath(filePath, fileName);
        String strFilePath = filePath + fileName;
        // 每次写入时，都换行写
        String strContent = strcontent + "\n";
        try {
            File file = new File(strFilePath);
            if (!file.exists()) {
                Log.d("TestFile", "Create the file:" + strFilePath);
                file.getParentFile().mkdirs();
                file.createNewFile();
            }
            RandomAccessFile raf = new RandomAccessFile(file, "rwd");
            raf.seek(file.length());
            raf.write(strContent.getBytes());
            raf.close();
        } catch (Exception e) {
            ToastUtils.show("请检查存储权限");
        }
    }

    //生成文件
    public static File makeFilePath(String filePath, String fileName) {
        File file = null;
        makeRootDirectory(filePath);
        try {
            file = new File(filePath + fileName);
            if (!file.exists()) {
                file.createNewFile();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return file;
    }

    //生成文件夹
    public static void makeRootDirectory(String filePath) {
        File file = null;
        try {
            file = new File(filePath);
            if (!file.exists()) {
                file.mkdir();
            }
        } catch (Exception e) {
            Log.i("error:", e + "");
        }
    }

    //读取指定目录下的所有TXT文件的文件内容
    public static String getFileContent(File file) {
        String content = "";
        if (!file.isDirectory()) {  //检查此路径名的文件是否是一个目录(文件夹)
            if (file.getName().endsWith("txt")) {//文件格式为""文件
                try {
                    InputStream instream = new FileInputStream(file);
                    if (instream != null) {
                        InputStreamReader inputreader
                                = new InputStreamReader(instream, "UTF-8");
                        BufferedReader buffreader = new BufferedReader(inputreader);
                        String line = "";
                        //分行读取
                        while ((line = buffreader.readLine()) != null) {
                            content += line + "";
                        }
                        instream.close();//关闭输入流
                    }
                } catch (java.io.FileNotFoundException e) {
                    Log.d("TestFile", "The File doesn't not exist.");
                } catch (IOException e) {
                    Log.d("TestFile", e.getMessage());
                }
            }
        }
        return content;
    }

    public static void DeleteFile(String path) {
        File file = new File(path);
        if (file.exists()) {
            file.deleteOnExit();
        }
    }

    public static void updateText(String strcontent, String filePath, String fileName) {
        makeFilePath(filePath, fileName);
        String strFilePath = filePath + fileName;
        String strContent = strcontent;
        try {
            File file = new File(strFilePath);
            if (!file.exists()) {
                file.getParentFile().mkdirs();
                file.createNewFile();
            }
            //写入的txt文档的路径
            PrintWriter pw = new PrintWriter(strFilePath);
            //写入的内容
            pw.write(strContent);
            pw.flush();
            pw.close();
        } catch (Exception e) {
            ToastUtils.show("请检查存储权限");
        }
    }

    /**
     * 读取changedata请求的id
     * @return 请求的id
     */
    public static String getXctId() {
        String id = getFileContent(new File("/sdcard/xct/id.txt"));
        return TextUtils.isEmpty(id) ? "0" : id;
    }

    /**
     * 保存changedata的id
     * @param id
     */
    public static void saveId(String id) {
        updateText(id, "/sdcard/xct/", "id.txt");
    }

    /**
     * 保存广告
     * @param advertStr
     */
    public static void saveAdvert(String advertStr){
        updateText(advertStr, "/sdcard/xct/", "advert.txt");
    }

    /**
     * 读取广告数据
     * @return
     */
    public static String getAdvert() {
        String advert = getFileContent(new File("/sdcard/xct/advert.txt"));
        return advert==null? "":advert;
    }
}