/**
 * 下载文件
 * 参数 [{图片路径(path)，自定义的图片名字(name)}...]
 */

public byte[] download(ArrayList pathList) {
    TrackerServer trackerServer = null;
    StorageServer storageServer = null;
    try {
        ClientGlobal.init("fdfs_client.properties");
        TrackerClient trackerClient = new TrackerClient();
        trackerServer = trackerClient.getConnection();
        storageServer = trackerClient.getStoreStorage(trackerServer);
        StorageClient storageClient = new StorageClient(trackerServer, storageServer);
        ArrayList list=pathList;
        for (int i = 0; i < list.size(); i++) {
            Map map = (Map) list.get(i);
            //获取 图片路径
            String pathMap = (String) map.get("path");
            //获取 图片名字
            String fileName = (String) map.get("name");
            //图片地址 例如：M00/00/01/wKgCYGDULuGATH2sAAD7vWJ6uiM234.jpg
            String path1 = pathMap.substring(7);
            //图片名字
            String reName = fileName;
            //返回一个流
            byte[] bytes = storageClient.download_file("group1", path1);
            String runPath = getRunPath();
            //文件名字
            String dirPath = runPath + "images";
            File dirFile = new File(dirPath);
            //如果文件夹不存在
            if (!dirFile.exists()) {
                //创建文件夹
                dirFile.mkdir();
            }
            //格式设置为UTF-8  避免出现乱码
            String name = new String(reName.getBytes("UTF-8"), "UTF-8");
            //生成文件路径
            String path = dirPath + File.separator;
            saveFile(bytes, path, name + ".jpg");
        }
    } catch (IOException e) {
        e.printStackTrace();
    } catch (MyException e) {
        e.printStackTrace();
    }
    return null;
}

//将字节流写到磁盘生成文件
private void saveFile(byte[] b, String path, String fileName) {

    File file = new File(path + fileName);
    FileOutputStream fileOutputStream = null;
    try {
        fileOutputStream = new FileOutputStream(file);

        fileOutputStream.write(b);

    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } finally {
        if (fileOutputStream != null) {
            try {
                fileOutputStream.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }

    }

}

/**
 * 生成zip文件，
 * 生成zip文件之前，先把之前的zip文件删掉。
 */
public long genZip() throws FileNotFoundException {

    String runPath = getRunPath();
    String dirPath = runPath + "images";
    String dirPathZip = runPath + "images.zip";
    if (FileUtil.exist(dirPathZip)) {//如果存在，就删除
        FileUtil.del(dirPathZip);
    }
    // 去压缩
    Charset charset = Charset.forName("UTF-8");
    File file = ZipUtil.zip(dirPath, charset);
    long length = file.length();
    if (file.exists()) {
        // 删除压缩前的
        FileUtil.del(dirPath);
    }
    return length;
}

// 返回下载链接
public String downLoadUrl() throws FileNotFoundException {
    System.out.println("调用下载链接");
    String runPath = getRunPath();
    String dirPath = runPath + "images.zip";
    System.out.println("要下载的文件链接为：");
    System.out.println(dirPath);
    return dirPath;
}

//执行完下载后，删除文件
public void deleteDic() throws FileNotFoundException {
    System.out.println("下载完成，开始删除");
    String runPath = getRunPath();
    String dirPath = runPath + "images.zip";
    FileUtil.del(dirPath);
}

public static String getRunPath() throws FileNotFoundException {
    String runPath = "/root/";
    if (FileUtil.isWindows()) {
        runPath = ResourceUtils.getURL(ResourceUtils.CLASSPATH_URL_PREFIX).getPath();
    }
    return runPath;
}