Retrofit(三)、使用Retrofit上传文件并带进度

在上一讲中 Retrofit(二)、使用Retrofit+OkHttp下载文件并带进度条 中，我们知道如何用Retrofit去下载文件并返回进度。细心的你会发现，其实Retrofit接口enqueue方法，最终也是调用了OkHttp的enqueue方法。这一讲，我们来实现通过Retrofit实现多文件上传并时时监听进度！

一、服务器端

在服务器端新增一个PostFileServlet的Servlet来接收多文件的上传与保存，代码如下：

@WebServlet("/PostFileServlet")
@MultipartConfig
public class PostFileServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;


    public PostFileServlet() {
        super();
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
     *      response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        this.doPost(request, response);
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
     *      response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        System.out.println("doPost==");
        request.setCharacterEncoding("utf-8");

        // 存储路径
        String savePath = "D:/huang/upload";
        // 把文件写到指定路径

        Collection<Part> parts = request.getParts();
        Iterator<Part> partIterator= parts.iterator();
        while(partIterator.hasNext()){
            Part part = partIterator.next();
            String heard = part.getHeader("content-disposition");
            String fileName = getFileName(heard);
            System.out.println(heard);
            part.write(savePath + File.separator + fileName);
        }

        response.setCharacterEncoding("UTF-8");
        PrintWriter writer = response.getWriter();
        writer.print("上传成功");
    }



    public String getFileName(String header) {

        String[] tempArr1 = header.split(";");

        String[] tempArr2 = tempArr1[2].split("=");
        // 获取文件名，兼容各种浏览器的写法
        String fileName = tempArr2[1].substring(tempArr2[1].lastIndexOf("\\") + 1).replaceAll("\"", "");
        return fileName;
    }

}

启动我们的服务器。

二、Android端

1.在上一讲 Retrofit(二)、使用Retrofit+OkHttp下载文件并带进度条 的RetrofitUtil类中添加以下方法：

  public static void postFileProgress(File file,File file2,final ProgressListener listener){


        MultipartBody.Builder muBuilder = new MultipartBody.Builder();
        muBuilder.addFormDataPart("file",file.getName(), RequestBody.create( MediaType.parse("multipart/form-data"),file));
        muBuilder.addFormDataPart("file2",file2.getName(), RequestBody.create( MediaType.parse("multipart/form-data"),file2));

        RequestBody originalRequestBody = muBuilder.build();
        ProgressRequestBody progressRequestBody = new ProgressRequestBody(originalRequestBody,listener);

        InterfaceRetrofit.PostFileRetrofit postFileRetrofit = retrofitBuilder.build().create(InterfaceRetrofit.PostFileRetrofit.class);
        postFileRetrofit.postFile(progressRequestBody).enqueue(new Callback<ResponseBody>() {
            @Override
            public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {

            }

            @Override
            public void onFailure(Call<ResponseBody> call, Throwable t) {

            }
        });
    }

2.上传文件接口PostFileRetrofit

 public interface PostFileRetrofit{

        @POST("PostFileServlet")
        Call<ResponseBody> postFile( @Body RequestBody partMap);
    }

3.ProgressRequestBody代码如:

public class ProgressRequestBody extends RequestBody {
    public static final int UPDATE = 0x01;
    private RequestBody requestBody;
    private ProgressListener mListener;
    private BufferedSink bufferedSink;
    private MyHandler myHandler;
    public ProgressRequestBody(RequestBody body, ProgressListener listener) {
        requestBody = body;
        mListener = listener;
        if (myHandler==null){
            myHandler = new MyHandler();
        }
    }

    class MyHandler extends Handler {

        public MyHandler() {
            super(Looper.getMainLooper());
        }

        @Override
        public void handleMessage(Message msg) {
            switch (msg.what){
                case UPDATE:
                    ProgressModel progressModel = (ProgressModel) msg.obj;
                    if (mListener!=null)mListener.onProgress(progressModel.getCurrentBytes(),progressModel.getContentLength(),progressModel.isDone());
                    break;

            }
        }


    }

    @Override
    public MediaType contentType() {
        return requestBody.contentType();
    }

    @Override
    public long contentLength() throws IOException {
        return requestBody.contentLength();
    }

    @Override
    public void writeTo(BufferedSink sink) throws IOException {

        if (bufferedSink==null){
            bufferedSink = Okio.buffer(sink(sink));
        }
        //写入
        requestBody.writeTo(bufferedSink);
        //刷新
        bufferedSink.flush();
    }

    private Sink sink(BufferedSink sink) {

        return new ForwardingSink(sink) {
            long bytesWritten = 0L;
            long contentLength = 0L;
            @Override
            public void write(Buffer source, long byteCount) throws IOException {
                super.write(source, byteCount);
                if (contentLength==0){
                    contentLength = contentLength();
                }
                bytesWritten += byteCount;
                //回调
                Message msg = Message.obtain();
                msg.what = UPDATE;
                msg.obj =  new ProgressModel(bytesWritten,contentLength,bytesWritten==contentLength);
                myHandler.sendMessage(msg);
            }
        };
    }


}

4.调用：

  RetrofitUtil.postFileProgress(new File(basePath + "/post1.jpg"), new File(basePath+"/post2.jpg"), new ProgressListener() {
                    @Override
                    public void onProgress(long currentBytes, long contentLength, boolean done) {
                        Log.i(TAG, "currentBytes==" + currentBytes + "==contentLength==" + contentLength + "==done==" + done);
                        int progress = (int) (currentBytes * 100 / contentLength);
                        refrofit_post_file_progress.setProgress(progress);
                    }
                });

5.服务器端log

doPost==
form-data; name="file"; filename="post1.jpg"
form-data; name="file2"; filename="post2.jpg"

同时在d盘的目录下可看到相应文件：

注：写的比较简单，如果不懂的话，请看源码或参照前几讲！:>

源码下载