起因
对于广大Android开发者来说，最近用的最多的网络库，莫过于Okhttp啦（Retrofit依赖Okhttp）。
Okhttp不像SDK内置的HttpUrlConnection一样，可以明确的获取数据读写的过程，我们需要执行一些操作。
介绍
Retrofit依赖Okhttp、Okhttp依赖于Okio。那么Okio又是什么鬼？别急，看官方介绍：
Okio is a library that complements java.io and java.nio to make it much easier to access, store, and process your data.
翻译过来就是，Okio是一个实现了java.io和java.nio的一个类库，它让连接，存储，处理你的数据更加轻松~（Okio既是读写相关类库，获取进度要从Okio入手）。
好吧，对于广大开发者来说，内心是这样的：TM又要看你文档和用例，按你规则走，轻松个毛啊！
其实，读下API，看下Example熟悉后，人家设计的还是很棒哒。
废话不多说，先看效果。
效果
tnetprogress-6.gif
实际代码：
//添加下载拦截器(this参数是实现下载进度接口的对象)
mDownClient = new OkHttpClient.Builder()
//只需要一行代码就行了
.addNetworkInterceptor(new DownloadInterceptor(this))
.build();
//添加上传拦截器(this参数是实现上传回调接口的对象)
mUploadClient = new OkHttpClient.Builder()
//只需要一行代码就行了
.addNetworkInterceptor(new UploadInterceptor(this))
.build();
你只需要一行代码是不行的！我为什么行？因为这是我写的封装类库啊~（最后放地址）
思路
Okhttp依赖Okio进行了数据的读写动作，我们需要找到Okio进行处理。那么，如何加上呢？
Okhttp可以添加Interceptor（拦截器），我们可以通过拦截器的接口方法，获取对应的responseBody、requestBody对象进行操作。然后我们就获取了读写相关的实现方法。具体实现是通过Source、Sink对象。
Source官方解释：Supplies a stream of bytes. Use this interface to read data from wherever it's located。
Sink官方解释：Receives a stream of bytes. Use this interface to write data wherever it's needed。
一句话概括：Source对象是对输入流的包装（下载读数据），Sink是对输出流的包装（写数据上传）。
实现
根据需要添加下载、上传Interceptor
//添加下载拦截器(this参数是实现下载进度接口的对象)
mDownClient = new OkHttpClient.Builder()
.addNetworkInterceptor(new DownloadInterceptor(this))
.build();
//添加上传拦截器(this参数是实现上传回调接口的对象)
mUploadClient = new OkHttpClient.Builder()
.addNetworkInterceptor(new UploadInterceptor(this))
.build();
拦截器具体实现
//下载拦截器
public class DownloadInterceptor implements Interceptor {
private OnDownloadListener mListener;
public DownloadInterceptor( OnDownloadListener listener) {
mListener = listener;
}
@Override
public Response intercept(Chain chain) throws IOException {
//封装ressponse对象
Response response = wrapResponse(chain.proceed(chain.request()));
return response;
}
private Response wrapResponse(Response response) {
if (response == null || response.body() == null) {
return response;
}
//获取处理后的response对象
Response wrapResponse = getWrapResponse(response);
return wrapResponse;
}
private Response getWrapResponse(Response response) {
ProgressInfo info = new ProgressInfo();
info.setTime(System.currentTimeMillis()+"");
info.setUrl(response.request().url().toString());
Response.Builder builder = response.newBuilder();
//封装responseBody，传入相关参数，获取进度数据回调
return builder.body(new WrapResponseBody(response.body(),info,mListener)).build();
}
}
--------------------------------------分割---------------------------------------
//上传拦截器
public class UploadInterceptor implements Interceptor {
private OnUploadListener mListener;
public UploadInterceptor(OnUploadListener listener) {
mListener = listener;
}
@Override
public Response intercept(Chain chain) throws IOException {
//封装request对象
Request request = wrapRequest(chain.request());
Response response = chain.proceed(request);
return response;
}
private Request wrapRequest(Request request) {
if (request == null || request.body() == null) {
return request;
}
Request.Builder builder = request.newBuilder();
ProgressInfo info = new ProgressInfo();
HttpUrl url = request.url();
info.setUrl(url.toString());
info.setTime(System.currentTimeMillis()+"");
//封装requestBody，传入参数，获取数据进度回调
builder.method(request.method(),new WrapRequestBody(request.body(),info,mListener));
return builder.build();
}
}
responseBody、requestBody相关实现
//继承ResponseBody实现具体方法
public class WrapResponseBody extends ResponseBody {
private Handler mHandler = new Handler(Looper.getMainLooper());
private ResponseBody mResponseBody;
private OnDownloadListener mListener;
private ProgressInfo mInfo;
private BufferedSource mBufferedSource;
private boolean mDoProgress;
//传入进度，以及监听对象
public WrapResponseBody(ResponseBody responseBody, ProgressInfo info, OnDownloadListener listener) {
mResponseBody = responseBody;
mInfo = info;
mListener = listener;
}
@Nullable
@Override
public MediaType contentType() {
//接口方法，返回类型
return mResponseBody.contentType();
}
@Override
public long contentLength() {
long contentLength = mResponseBody.contentLength();
//gzip压缩格式会返回-1，目前处理是在请求头信息指定("Accept-Encoding","identity")表示不压缩
if (contentLength == -1) {
mDoProgress = false;
mHandler.post(new Runnable() {
@Override
public void run() {
//切换线程，进行失败回调
mListener.onDownLoadGetContentLengthFail(mInfo);
}
});
} else {
mDoProgress = true;
}
return contentLength;
}
@Override
public BufferedSource source() {
//WrapSource（继承ForwardingSource，ForwardingSource实现了Source接口）
if (mBufferedSource == null) {
mInfo.setContentLength(contentLength());
//传入参数，读取具体进度信息，并回调
WrapSource wrapSource = new WrapSource(mResponseBody.source(), mInfo, mListener,mDoProgress);
mBufferedSource = Okio.buffer(wrapSource);
}
return mBufferedSource;
}
}
--------------------------------------分割---------------------------------------
//继承ResquestBody实现具体方法
public class WrapRequestBody extends RequestBody {
private RequestBody mRequestBody;
private OnUploadListener mListener;
private ProgressInfo mInfo;
private boolean mDoProgress;
private Handler mHandler = new Handler(Looper.getMainLooper());
//传入进度，以及监听对象
public WrapRequestBody(RequestBody requestBody, ProgressInfo info, OnUploadListener listener) {
mRequestBody = requestBody;
mListener = listener;
mInfo = info;
}
@Override
public MediaType contentType() {
//接口方法，返回类型
return mRequestBody.contentType();
}
@Override
public long contentLength() throws IOException {
try {
//上传内容长度，有异常走failWrok处理
long l = mRequestBody.contentLength();
mDoProgress = true;
return l;
} catch (IOException e) {
e.printStackTrace();
failWork();
return -1;
}
}
//进行失败处理
private void failWork() {
mDoProgress = false;
mHandler.post(new Runnable() {
@Override
public void run() {
//切换线程，回调失败信息
mListener.onUploadGetContentLengthFail(mInfo);
}
});
}
@Override
public void writeTo(BufferedSink sink) throws IOException {
mInfo.setContentLength(contentLength());
// WrapSink （继承ForwardingSink，ForwardingSink实现了Sink接口）
///传入参数，读取具体进度信息，并回调
WrapSink wrapSink = new WrapSink(sink, mInfo, mListener, mDoProgress);
BufferedSink buffer = Okio.buffer(wrapSink);
mRequestBody.writeTo(buffer);
buffer.flush();
}
}
WrapSource、WrapSink相关实现
//继承ForwardingSource 实现具体方法
public class WrapSource extends ForwardingSource {
private Handler mHandler = new Handler(Looper.getMainLooper());
private Source mSource;
private ProgressInfo mInfo;
private OnDownloadListener mListener;
private boolean mDoProgress;
public WrapSource(Source source, ProgressInfo info, OnDownloadListener listener, boolean doProgress) {
//传入源Source、进度信息、监听进度等信息。
super(source);
mSource = source;
mInfo = info;
mListener = listener;
//传入是否继续执行回调boolean参数，如果之前执行有异常，则不再继续执行回调
mDoProgress = doProgress;
}
@Override
public long read(Buffer sink, long byteCount) throws IOException {
//获取具体进度信息，来到了熟悉的具体IO
long read = super.read(sink, byteCount);
if (read != -1) {
long l = mInfo.getCurrentLength() + read;
mInfo.setCurrentLength(l);
mHandler.post(new Runnable() {
@Override
public void run() {
if (mDoProgress) {
//切换到主线程，回调数据
mListener.onDownLoadProgress(mInfo);
}
}
});
}
return read;
}
}
--------------------------------------分割---------------------------------------
//继承ForwardingSink 实现具体方法
public class WrapSink extends ForwardingSink {
private Handler mHandler = new Handler(Looper.getMainLooper());
public OnUploadListener mListener;
public ProgressInfo mInfo;
public boolean mDoProgress;
public WrapSink(Sink delegate, ProgressInfo info, OnUploadListener listener, boolean doProgress) {
//传入源Source、进度信息、监听进度等信息。
super(delegate);
mInfo = info;
mListener = listener;
//传入是否继续执行回调boolean参数，如果之前执行有异常，则不再继续执行回调
mDoProgress = doProgress;
}
@Override
public void write(Buffer source, long byteCount) throws IOException {
super.write(source, byteCount);
//获取具体进度信息，来到了熟悉的具体IO
long l = mInfo.getCurrentLength() + byteCount;
mInfo.setCurrentLength(l);
mHandler.post(new Runnable() {
@Override
public void run() {
if (mDoProgress) {
//切换到主线程，回调数据
mListener.onUpLoadProgress(mInfo);
}
}
});
}
}
总结
以上就是具体的流程了，按照步骤其实很简单。大家了解下挺好的，我这边也封装好了具体的类库和Demo，大家可以直接依赖（查看README.md，使用简单）。
地址：https://github.com/HoldMyOwn/TNetProgress
网友评论
//内部代码不展示,突出重点.这个方法传入了实参subscriber对象(下载写法类似)
//写的比较早的库,暂时是rxjava1.x
}