跟大家讲一个笑话,我维护老项目,看到有一个清除缓存功能,我看了一下怎么实现的，结果就一个Toast太逗比了

    /**
     * 获取指定文件夹的大小
     *
     * @param f
     * @return
     * @throws Exception
     */
    public static long getFileSizes(File f) {
        long size = 0;
        File flist[] = f.listFiles();//文件夹目录下的所有文件
        if (flist == null) {//4.2的模拟器空指针。
            return 0;
        }
        if (flist != null) {
            for (int i = 0; i < flist.length; i++) {
                if (flist[i].isDirectory()) {//判断是否父目录下还有子目录
                    size = size + getFileSizes(flist[i]);
                } else {
                    size = size + getFileSize(flist[i]);
                }
            }
        }
        return size;
    }

获取文件大小

    }

    /**
     * 获取指定文件的大小
     *
     * @return
     * @throws Exception
     */
    public static long getFileSize(File file) {

        long size = 0;
        if (file.exists()) {
            FileInputStream fis = null;
            try {
                fis = new FileInputStream(file);//使用FileInputStream读入file的数据流
                size = fis.available();//文件的大小
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    fis.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

        } else {
        }
        return size;
    }

计算当前应用缓存文件夹

     File file1 = AppContext.getInstance().getCacheDir();
                File file2 = AppContext.getInstance().getExternalCacheDir();
                long fileSizes = FileUtils.getFileSizes(file1);
                long fileSizes2 = FileUtils.getFileSizes(file2);
                return fileSizes + fileSizes2;

清除所有缓存

   public static boolean clearAllCache() {
        File externalCacheDir = SuperAppContext.getInstance().getExternalCacheDir();
        File cacheDir = SuperAppContext.getInstance().getCacheDir();
        boolean result = false;
        if (cacheDir != null) {
            result = delAllFile(cacheDir.getAbsolutePath());
        }
        if (externalCacheDir != null) {

            result = delAllFile(externalCacheDir.getAbsolutePath()) || result ? true : false;//原生是真 或者现在是true就是true
        }
        return result;
    }

删除文件夹

    //删除指定文件夹下所有文件
//param path 文件夹完整绝对路径
    public static boolean delAllFile(String path) {
        boolean flag = false;
        File file = new File(path);
        if (!file.exists()) {
            return flag;
        }
        if (!file.isDirectory()) {
            return flag;
        }
        String[] tempList = file.list();
        File temp = null;
        for (int i = 0; i < tempList.length; i++) {
            if (path.endsWith(File.separator)) {
                temp = new File(path + tempList[i]);
            } else {
                temp = new File(path + File.separator + tempList[i]);
            }
            if (temp.isFile()) {
                temp.delete();
            }
            if (temp.isDirectory()) {
                delAllFile(path + "/" + tempList[i]);//先删除文件夹里面的文件
                delFolder(path + "/" + tempList[i]);//再删除空文件夹
                flag = true;
            }
        }
        return flag;
    }

删除volley, uiversalCache文件夹

   public static File getVolleyCacheFile() {
        return productSystemCacheFolder("volley");
    }

    public static File getImageUniversalCacheFile() {
        return productSystemCacheFolder("uil-images");
    }