目录介绍

• 01.先提问一个问题
• 02.EventListener回调原理
• 03.请求开始结束监听
• 04.dns解析开始结束监听
• 05.连接开始结束监听
• 06.TLS连接开始结束监听
• 07.连接绑定和释放监听
• 08.request请求监听
• 09.response响应监听
• 10.如何监听统计耗时
• 11.应用实践之案例

01.先提问一个问题

• OkHttp如何进行各个请求环节的耗时统计呢？
  • OkHttp 版本提供了EventListener接口，可以让调用者接收一系列网络请求过程中的事件，例如DNS解析、TSL/SSL连接、Response接收等。
  • 通过继承此接口，调用者可以监视整个应用中网络请求次数、流量大小、耗时(比如dns解析时间，请求时间，响应时间等等)情况。

02.EventListener回调原理

• 先来看一下

  public abstract class EventListener {
     // 按照请求顺序回调
      public void callStart(Call call) {}
      // 域名解析
      public void dnsStart(Call call, String domainName) {}
      public void dnsEnd(Call call, String domainName, List<InetAddress> inetAddressList) {}
      // 释放当前Transmitter的RealConnection
      public void connectionReleased(Call call, Connection connection) {}
      public void connectionAcquired(call, result){};
      // 开始连接
      public void connectStart(call, route.socketAddress(), proxy){}
      // 请求
      public void requestHeadersStart(@NotNull Call call){}
      public void requestHeadersEnd(@NotNull Call call, @NotNull Request request) {}
      // 响应
      public void requestBodyStart(@NotNull Call call) {}
      public void requestBodyEnd(@NotNull Call call, long byteCount) {}
      // 结束
      public void callEnd(Call call) {}
      // 失败
      public void callFailed(Call call, IOException ioe) {}
  }
  

03.请求开始结束监听

• callStart(Call call) 请求开始
  • 当一个Call（代表一个请求）被同步执行或被添加异步队列中时，即会调用这个回调方法。
  • 需要说明这个方法是在dispatcher.executed/enqueue前执行的。
  • 由于线程或事件流的限制，这里的请求开始并不是真正的去执行的这个请求。如果发生重定向和多域名重试时，这个方法也仅被调用一次。

  final class RealCall implements Call {
      @Override 
      public Response execute() throws IOException {
          eventListener.callStart(this);
          client.dispatcher().executed(this);
          Response result = getResponseWithInterceptorChain();
          if (result == null) throw new IOException("Canceled");
          return result;    
      }
  
      @Override 
      public void enqueue(Callback responseCallback) {
          eventListener.callStart(this);
          client.dispatcher().enqueue(new AsyncCall(responseCallback));
      }
  }
  

• callFailed/callEnd 请求异常和请求结束
  • 每一个callStart都对应着一个callFailed或callEnd。
  • callFailed在两种情况下被调用，第一种是在请求执行的过程中发生异常时。第二种是在请求结束后，关闭输入流时产生异常时。

  final class RealCall implements Call {
      @Override 
      public Response execute() throws IOException {
          try {
            client.dispatcher().executed(this);
            Response result = getResponseWithInterceptorChain();
            if (result == null) throw new IOException("Canceled");
            return result;
          } catch (IOException e) {
            eventListener.callFailed(this, e);
            throw e;
          }
      }
      final class AsyncCall extends NamedRunnable {
          @Override 
          protected void execute() {
              try {
                  Response response = getResponseWithInterceptorChain();
              } catch (IOException e) {
                  eventListener.callFailed(RealCall.this, e);
  
              }
          }
      }
  }
  
  //第二种
  public final class StreamAllocation {
      public void streamFinished(boolean noNewStreams, HttpCodec codec, long bytesRead, IOException e) {
          ...
          if (e != null) {
            eventListener.callFailed(call, e);
          } else if (callEnd) {
            eventListener.callEnd(call);
          }
          ...
      }
  }
  

  • callEnd也有两种调用场景。第一种也是在关闭流时。第二种是在释放连接时。

  public final class StreamAllocation {
  
      public void streamFinished(boolean noNewStreams, HttpCodec codec, long bytesRead, IOException e) {
          ...
          if (e != null) {
            eventListener.callFailed(call, e);
          } else if (callEnd) {
            eventListener.callEnd(call);
          }
          ...
      }
  
      public void release() {
          ...
          if (releasedConnection != null) {
            eventListener.connectionReleased(call, releasedConnection);
            eventListener.callEnd(call);
          }
      }
  }
  

  • 为什么会将关闭流和关闭连接区分开？
    • 在http2版本中，一个连接上允许打开多个流，OkHttp使用StreamAllocation来作为流和连接的桥梁。当一个流被关闭时，要检查这条连接上还有没有其他流，如果没有其他流了，则可以将连接关闭了。
    • streamFinished和release作用是一样的，都是关闭当前流，并检查是否需要关闭连接。不同的是，当调用者手动取消请求时，调用的是release方法，并由调用者负责关闭请求输出流和响应输入流。

04.dns解析开始结束监听

• dnsStart开始
  • 其中的lookup(String hostname)方法代表了域名解析的过程，dnsStart/dnsEnd就是在lookup前后被调用的
  • DNS解析是请求DNS（Domain Name System）服务器，将域名解析成ip的过程。域名解析工作是由JDK中的InetAddress类完成的。

    /** Prepares the socket addresses to attempt for the current proxy or host. */
    private void resetNextInetSocketAddress(Proxy proxy) throws IOException {
      if (proxy.type() == Proxy.Type.SOCKS) {
        inetSocketAddresses.add(InetSocketAddress.createUnresolved(socketHost, socketPort));
      } else {
        eventListener.dnsStart(call, socketHost);
  
        // Try each address for best behavior in mixed IPv4/IPv6 environments.
        List<InetAddress> addresses = address.dns().lookup(socketHost);
        if (addresses.isEmpty()) {
          throw new UnknownHostException(address.dns() + " returned no addresses for " + socketHost);
        }
  
        eventListener.dnsEnd(call, socketHost, addresses);
      }
    }
  

• 那么RouteSelector这个类是在哪里调用

  public final class StreamAllocation {
  
    public StreamAllocation(ConnectionPool connectionPool, Address address, Call call,
        EventListener eventListener, Object callStackTrace) {
      this.routeSelector = new RouteSelector(address, routeDatabase(), call, eventListener);
    }
  }
  

05.连接开始结束监听

• connectStart连接开始
  • OkHttp是使用Socket接口建立Tcp连接的，所以这里的连接就是指Socket建立一个连接的过程。
  • 当连接被重用时，connectStart/connectEnd不会被调用。当请求被重定向到新的域名后，connectStart/connectEnd会被调用多次。

    private void connectSocket(int connectTimeout, int readTimeout, Call call,
        EventListener eventListener) throws IOException {
      Proxy proxy = route.proxy();
      Address address = route.address();
  
      rawSocket = proxy.type() == Proxy.Type.DIRECT || proxy.type() == Proxy.Type.HTTP
          ? address.socketFactory().createSocket()
          : new Socket(proxy);
  
      eventListener.connectStart(call, route.socketAddress(), proxy);
    }
  

• connectEnd连接结束
  • 因为创建的连接有两种类型（服务端直连和隧道代理），所以callEnd有两处调用位置。为了在基于代理的连接上使用SSL，需要单独发送CONECT请求。
  • 在连接过程中，无论是Socket连接失败，还是TSL/SSL握手失败，都会回调connectEnd。

    public void connect(int connectTimeout, int readTimeout, int writeTimeout,
      while (true) {
        try {
          establishProtocol(connectionSpecSelector, pingIntervalMillis, call, eventListener);
          eventListener.connectEnd(call, route.socketAddress(), route.proxy(), protocol);
          break;
        } catch (IOException e) {
          eventListener.connectFailed(call, route.socketAddress(), route.proxy(), null, e);
        }
    }
  
    private void connectTunnel(int connectTimeout, int readTimeout, int writeTimeout, Call call,
        EventListener eventListener) throws IOException {
      Request tunnelRequest = createTunnelRequest();
      HttpUrl url = tunnelRequest.url();
      for (int i = 0; i < MAX_TUNNEL_ATTEMPTS; i++) {
        connectSocket(connectTimeout, readTimeout, call, eventListener);
        eventListener.connectEnd(call, route.socketAddress(), route.proxy(), null);
      }
    }
  

06.TLS连接开始结束监听

• 开始连接，代码如下所示
  • 在上面看到，在Socket建立连接后，会执行一个establishProtocol方法，这个方法的作用就是TSL/SSL握手。
  • 当存在重定向或连接重试的情况下，secureConnectStart/secureConnectEnd会被调用多次。

    private void establishProtocol(ConnectionSpecSelector connectionSpecSelector,
        int pingIntervalMillis, Call call, EventListener eventListener) throws IOException {
      if (route.address().sslSocketFactory() == null) {
        protocol = Protocol.HTTP_1_1;
        socket = rawSocket;
        return;
      }
  
      eventListener.secureConnectStart(call);
      connectTls(connectionSpecSelector);
      eventListener.secureConnectEnd(call, handshake);
    }
  

• 结合连接监听可知
  • 如果我们使用了HTTPS安全连接，在TCP连接成功后需要进行TLS安全协议通信，等TLS通讯结束后才能算是整个连接过程的结束，也就是说connectEnd在secureConnectEnd之后调用。
• 所以顺序是这样的
  • connectStart ---> secureConnectStart ---> secureConnectEnd ---> ConnectEnd

07.连接绑定和释放监听

• 因为OkHttp是基于连接复用的，当一次请求结束后并不会马上关闭当前连接，而是放到连接池中。
  • 当有相同域名的请求时，会从连接池中取出对应的连接使用，减少了连接的频繁创建和销毁。
  • 当根据一个请求从连接池取连接时，并打开输入输出流就是acquired，用完释放流就是released。
  • 如果直接复用StreamAllocation中的连接，则不会调用connectionAcquired/connectReleased。

    private RealConnection findConnection(int connectTimeout, int readTimeout, int writeTimeout,
        int pingIntervalMillis, boolean connectionRetryEnabled) throws IOException {
      synchronized (connectionPool) {
        if (result == null) {
          // 第一次查缓存 Attempt to get a connection from the pool.
          // Attempt to get a connection from the pool.
          Internal.instance.get(connectionPool, address, this, null);
        }
      }
  
      if (releasedConnection != null) {
        eventListener.connectionReleased(call, releasedConnection);
      }
      if (foundPooledConnection) {
        eventListener.connectionAcquired(call, result);
      }
  
      synchronized (connectionPool) {
        if (canceled) throw new IOException("Canceled");
  
        if (newRouteSelection) {
          //第二次查缓存
          List<Route> routes = routeSelection.getAll();
          for (int i = 0, size = routes.size(); i < size; i++) {
            Route route = routes.get(i);
            Internal.instance.get(connectionPool, address, this, route);
            if (connection != null) {
              foundPooledConnection = true;
              result = connection;
              this.route = route;
              break;
            }
          }
        }
  
        if (!foundPooledConnection) {
          //如果缓存没有，则新建连接
          route = selectedRoute;
          refusedStreamCount = 0;
          result = new RealConnection(connectionPool, selectedRoute);
          acquire(result, false);
        }
      }
  
      // If we found a pooled connection on the 2nd time around, we're done.
      if (foundPooledConnection) {
        eventListener.connectionAcquired(call, result);
        return result;
      }
  
      // Do TCP + TLS handshakes. This is a blocking operation.
      result.connect(connectTimeout, readTimeout, writeTimeout, pingIntervalMillis,
          connectionRetryEnabled, call, eventListener);
      routeDatabase().connected(result.route());
  
      eventListener.connectionAcquired(call, result);
      return result;
    }
  

• connectionAcquired是在连接成功后被调用的。
  • 但是在连接复用的情况下没有连接步骤，connectAcquired会在获取缓存连接后被调用。由于StreamAllocation是连接“Stream”和“Connection”的桥梁，所以在StreamAllocation中会持有一个RealConnection引用。StreamAllocation在查找可用连接的顺序为：StreamAllocation.RealConnection -> ConnectionPool -> ConnectionPool -> new RealConnection

08.request请求监听

• 在OkHttp中，HttpCodec负责对请求和响应按照Http协议进行编解码，包含发送请求头、发送请求体、读取响应头、读取响应体。
• requestHeaders开始和结束，这个直接看CallServerInterceptor拦截器代码即可。

  public final class CallServerInterceptor implements Interceptor {
  
    @Override public Response intercept(Chain chain) throws IOException {
      RealInterceptorChain realChain = (RealInterceptorChain) chain;
      HttpCodec httpCodec = realChain.httpStream();
      StreamAllocation streamAllocation = realChain.streamAllocation();
      RealConnection connection = (RealConnection) realChain.connection();
      Request request = realChain.request();
  
      long sentRequestMillis = System.currentTimeMillis();
  
      realChain.eventListener().requestHeadersStart(realChain.call());
      httpCodec.writeRequestHeaders(request);
      realChain.eventListener().requestHeadersEnd(realChain.call(), request);
  
      if (HttpMethod.permitsRequestBody(request.method()) && request.body() != null) {
        if (responseBuilder == null) {
          // Write the request body if the "Expect: 100-continue" expectation was met.
          realChain.eventListener().requestBodyStart(realChain.call());
          long contentLength = request.body().contentLength();
          CountingSink requestBodyOut =
              new CountingSink(httpCodec.createRequestBody(request, contentLength));
          BufferedSink bufferedRequestBody = Okio.buffer(requestBodyOut);
  
          request.body().writeTo(bufferedRequestBody);
          bufferedRequestBody.close();
          realChain.eventListener().requestBodyEnd(realChain.call(), requestBodyOut.successfulCount);
        } 
      }
      return response;
    }
  }
  

09.response响应监听

• responseHeadersStart和responseHeadersEnd代码如下所示

  public final class CallServerInterceptor implements Interceptor {
  
    @Override public Response intercept(Chain chain) throws IOException {
  
      Response.Builder responseBuilder = null;
      if (HttpMethod.permitsRequestBody(request.method()) && request.body() != null) {
        if ("100-continue".equalsIgnoreCase(request.header("Expect"))) {
          httpCodec.flushRequest();
          realChain.eventListener().responseHeadersStart(realChain.call());
          responseBuilder = httpCodec.readResponseHeaders(true);
        }
      }
  
      httpCodec.finishRequest();
  
      if (responseBuilder == null) {
        realChain.eventListener().responseHeadersStart(realChain.call());
        responseBuilder = httpCodec.readResponseHeaders(false);
      }
  
      int code = response.code();
      if (code == 100) {
        // server sent a 100-continue even though we did not request one.
        // try again to read the actual response
        responseBuilder = httpCodec.readResponseHeaders(false);
  
        response = responseBuilder
                .request(request)
                .handshake(streamAllocation.connection().handshake())
                .sentRequestAtMillis(sentRequestMillis)
                .receivedResponseAtMillis(System.currentTimeMillis())
                .build();
  
        code = response.code();
      }
  
      realChain.eventListener() .responseHeadersEnd(realChain.call(), response);
      return response;
    }
  }
  

• responseBodyStart监听
  • 响应体的读取有些复杂，要根据不同类型的Content-Type决定如何读取响应体，例如固定长度的、基于块(chunk)数据的、未知长度的。具体看openResponseBody方法里面的代码。
  • 同时Http1与Http2也有不同的解析方式。下面以Http1为例。

  public final class Http1Codec implements HttpCodec {
  
    @Override public ResponseBody openResponseBody(Response response) throws IOException {
      streamAllocation.eventListener.responseBodyStart(streamAllocation.call);
      String contentType = response.header("Content-Type");
  
      if (!HttpHeaders.hasBody(response)) {
        Source source = newFixedLengthSource(0);
        return new RealResponseBody(contentType, 0, Okio.buffer(source));
      }
  
      if ("chunked".equalsIgnoreCase(response.header("Transfer-Encoding"))) {
        Source source = newChunkedSource(response.request().url());
        return new RealResponseBody(contentType, -1L, Okio.buffer(source));
      }
  
      long contentLength = HttpHeaders.contentLength(response);
      if (contentLength != -1) {
        Source source = newFixedLengthSource(contentLength);
        return new RealResponseBody(contentType, contentLength, Okio.buffer(source));
      }
  
      return new RealResponseBody(contentType, -1L, Okio.buffer(newUnknownLengthSource()));
    }
  }
  

• responseBodyEnd监听
  • 由下面代码可知，当响应结束后，会调用连接callEnd回调（如果异常则会调用callFailed回调）

  public final class StreamAllocation {
    public void streamFinished(boolean noNewStreams, HttpCodec codec, long bytesRead, IOException e) {
      eventListener.responseBodyEnd(call, bytesRead);
      if (releasedConnection != null) {
        eventListener.connectionReleased(call, releasedConnection);
      }
      if (e != null) {
        eventListener.callFailed(call, e);
      } else if (callEnd) {
        eventListener.callEnd(call);
      }
    }
  }
  

10.如何监听统计耗时

• 如何消耗记录时间
  • 在OkHttp库中有一个EventListener类。该类是网络事件的侦听器。扩展这个类以监视应用程序的HTTP调用的数量、大小和持续时间。
  • 所有启动/连接/获取事件最终将接收到匹配的结束/释放事件，要么成功(非空参数)，要么失败(非空可抛出)。
  • 比如，可以在开始链接记录时间；dns开始，结束等方法解析记录时间，可以计算dns的解析时间。
  • 比如，可以在开始请求记录时间，记录connectStart，connectEnd等方法时间，则可以计算出connect连接时间。
• 代码如下所示
  • Eventlistener只适用于没有并发的情况，如果有多个请求并发执行我们需要使用Eventlistener. Factory来给每个请求创建一个Eventlistener。
  • 这个mRequestId是唯一值，可以选择使用AtomicInteger自增+1的方式设置id，这个使用了cas保证多线程条件下的原子性特性。

  /**
   * <pre>
   *     @author yangchong
   *     email  : yangchong211@163.com
   *     time  : 2019/07/22
   *     desc  : EventListener子类
   *     revise:
   * </pre>
   */
  public class NetworkListener extends EventListener {
  
      private static final String TAG = "NetworkEventListener";
      private static AtomicInteger mNextRequestId = new AtomicInteger(0);
      private String mRequestId ;
  
      public static Factory get(){
          Factory factory = new Factory() {
              @NotNull
              @Override
              public EventListener create(@NotNull Call call) {
                  return new NetworkListener();
              }
          };
          return factory;
      }
  
      @Override
      public void callStart(@NotNull Call call) {
          super.callStart(call);
          //mRequestId = mNextRequestId.getAndIncrement() + "";
          //getAndAdd，在多线程下使用cas保证原子性
          mRequestId = String.valueOf(mNextRequestId.getAndIncrement());
          ToolLogUtils.i(TAG+"-------callStart---requestId-----"+mRequestId);
          saveEvent(NetworkTraceBean.CALL_START);
          saveUrl(call.request().url().toString());
      }
  
      @Override
      public void dnsStart(@NotNull Call call, @NotNull String domainName) {
          super.dnsStart(call, domainName);
          ToolLogUtils.d(TAG, "dnsStart");
          saveEvent(NetworkTraceBean.DNS_START);
      }
  
      @Override
      public void dnsEnd(@NotNull Call call, @NotNull String domainName, @NotNull List<InetAddress> inetAddressList) {
          super.dnsEnd(call, domainName, inetAddressList);
          ToolLogUtils.d(TAG, "dnsEnd");
          saveEvent(NetworkTraceBean.DNS_END);
      }
  
      @Override
      public void connectStart(@NotNull Call call, @NotNull InetSocketAddress inetSocketAddress, @NotNull Proxy proxy) {
          super.connectStart(call, inetSocketAddress, proxy);
          ToolLogUtils.d(TAG, "connectStart");
          saveEvent(NetworkTraceBean.CONNECT_START);
      }
  
      @Override
      public void secureConnectStart(@NotNull Call call) {
          super.secureConnectStart(call);
          ToolLogUtils.d(TAG, "secureConnectStart");
          saveEvent(NetworkTraceBean.SECURE_CONNECT_START);
      }
  
      @Override
      public void secureConnectEnd(@NotNull Call call, @Nullable Handshake handshake) {
          super.secureConnectEnd(call, handshake);
          ToolLogUtils.d(TAG, "secureConnectEnd");
          saveEvent(NetworkTraceBean.SECURE_CONNECT_END);
      }
  
      @Override
      public void connectEnd(@NotNull Call call, @NotNull InetSocketAddress inetSocketAddress,
                             @NotNull Proxy proxy, @Nullable Protocol protocol) {
          super.connectEnd(call, inetSocketAddress, proxy, protocol);
          ToolLogUtils.d(TAG, "connectEnd");
          saveEvent(NetworkTraceBean.CONNECT_END);
      }
  
      @Override
      public void connectFailed(@NotNull Call call, @NotNull InetSocketAddress inetSocketAddress, @NotNull Proxy proxy, @Nullable Protocol protocol, @NotNull IOException ioe) {
          super.connectFailed(call, inetSocketAddress, proxy, protocol, ioe);
          ToolLogUtils.d(TAG, "connectFailed");
      }
  
      @Override
      public void requestHeadersStart(@NotNull Call call) {
          super.requestHeadersStart(call);
          ToolLogUtils.d(TAG, "requestHeadersStart");
          saveEvent(NetworkTraceBean.REQUEST_HEADERS_START);
      }
  
      @Override
      public void requestHeadersEnd(@NotNull Call call, @NotNull Request request) {
          super.requestHeadersEnd(call, request);
          ToolLogUtils.d(TAG, "requestHeadersEnd");
          saveEvent(NetworkTraceBean.REQUEST_HEADERS_END);
      }
  
      @Override
      public void requestBodyStart(@NotNull Call call) {
          super.requestBodyStart(call);
          ToolLogUtils.d(TAG, "requestBodyStart");
          saveEvent(NetworkTraceBean.REQUEST_BODY_START);
      }
  
      @Override
      public void requestBodyEnd(@NotNull Call call, long byteCount) {
          super.requestBodyEnd(call, byteCount);
          ToolLogUtils.d(TAG, "requestBodyEnd");
          saveEvent(NetworkTraceBean.REQUEST_BODY_END);
      }
  
      @Override
      public void responseHeadersStart(@NotNull Call call) {
          super.responseHeadersStart(call);
          ToolLogUtils.d(TAG, "responseHeadersStart");
          saveEvent(NetworkTraceBean.RESPONSE_HEADERS_START);
      }
  
      @Override
      public void responseHeadersEnd(@NotNull Call call, @NotNull Response response) {
          super.responseHeadersEnd(call, response);
          ToolLogUtils.d(TAG, "responseHeadersEnd");
          saveEvent(NetworkTraceBean.RESPONSE_HEADERS_END);
      }
  
      @Override
      public void responseBodyStart(@NotNull Call call) {
          super.responseBodyStart(call);
          ToolLogUtils.d(TAG, "responseBodyStart");
          saveEvent(NetworkTraceBean.RESPONSE_BODY_START);
      }
  
      @Override
      public void responseBodyEnd(@NotNull Call call, long byteCount) {
          super.responseBodyEnd(call, byteCount);
          ToolLogUtils.d(TAG, "responseBodyEnd");
          saveEvent(NetworkTraceBean.RESPONSE_BODY_END);
      }
  
      @Override
      public void callEnd(@NotNull Call call) {
          super.callEnd(call);
          ToolLogUtils.d(TAG, "callEnd");
          saveEvent(NetworkTraceBean.CALL_END);
          generateTraceData();
          NetWorkUtils.timeoutChecker(mRequestId);
      }
  
      @Override
      public void callFailed(@NotNull Call call, @NotNull IOException ioe) {
          super.callFailed(call, ioe);
          ToolLogUtils.d(TAG, "callFailed");
      }
  
      private void generateTraceData(){
          NetworkTraceBean traceModel = IDataPoolHandleImpl.getInstance().getNetworkTraceModel(mRequestId);
          Map<String, Long> eventsTimeMap = traceModel.getNetworkEventsMap();
          Map<String, Long> traceList = traceModel.getTraceItemList();
          traceList.put(NetworkTraceBean.TRACE_NAME_TOTAL,NetWorkUtils.getEventCostTime(eventsTimeMap,NetworkTraceBean.CALL_START, NetworkTraceBean.CALL_END));
          traceList.put(NetworkTraceBean.TRACE_NAME_DNS,NetWorkUtils.getEventCostTime(eventsTimeMap,NetworkTraceBean.DNS_START, NetworkTraceBean.DNS_END));
          traceList.put(NetworkTraceBean.TRACE_NAME_SECURE_CONNECT,NetWorkUtils.getEventCostTime(eventsTimeMap,NetworkTraceBean.SECURE_CONNECT_START, NetworkTraceBean.SECURE_CONNECT_END));
          traceList.put(NetworkTraceBean.TRACE_NAME_CONNECT,NetWorkUtils.getEventCostTime(eventsTimeMap,NetworkTraceBean.CONNECT_START, NetworkTraceBean.CONNECT_END));
          traceList.put(NetworkTraceBean.TRACE_NAME_REQUEST_HEADERS,NetWorkUtils.getEventCostTime(eventsTimeMap,NetworkTraceBean.REQUEST_HEADERS_START, NetworkTraceBean.REQUEST_HEADERS_END));
          traceList.put(NetworkTraceBean.TRACE_NAME_REQUEST_BODY,NetWorkUtils.getEventCostTime(eventsTimeMap,NetworkTraceBean.REQUEST_BODY_START, NetworkTraceBean.REQUEST_BODY_END));
          traceList.put(NetworkTraceBean.TRACE_NAME_RESPONSE_HEADERS,NetWorkUtils.getEventCostTime(eventsTimeMap,NetworkTraceBean.RESPONSE_HEADERS_START, NetworkTraceBean.RESPONSE_HEADERS_END));
          traceList.put(NetworkTraceBean.TRACE_NAME_RESPONSE_BODY,NetWorkUtils.getEventCostTime(eventsTimeMap,NetworkTraceBean.RESPONSE_BODY_START, NetworkTraceBean.RESPONSE_BODY_END));
      }
  
      private void saveEvent(String eventName){
          NetworkTraceBean networkTraceModel = IDataPoolHandleImpl.getInstance().getNetworkTraceModel(mRequestId);
          Map<String, Long> networkEventsMap = networkTraceModel.getNetworkEventsMap();
          networkEventsMap.put(eventName, SystemClock.elapsedRealtime());
      }
  
      private void saveUrl(String url){
          NetworkTraceBean networkTraceModel = IDataPoolHandleImpl.getInstance().getNetworkTraceModel(mRequestId);
          networkTraceModel.setUrl(url);
      }
  
  }
  

• 关于执行顺序，打印结果如下所示

  2020-09-22 20:50:15.351 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: dnsStart
  2020-09-22 20:50:15.373 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: dnsEnd
  2020-09-22 20:50:15.374 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: connectStart
  2020-09-22 20:50:15.404 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: secureConnectStart
  2020-09-22 20:50:15.490 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: secureConnectEnd
  2020-09-22 20:50:15.490 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: connectEnd
  2020-09-22 20:50:15.492 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: requestHeadersStart
  2020-09-22 20:50:15.492 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: requestHeadersEnd
  2020-09-22 20:50:15.528 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: responseHeadersStart
  2020-09-22 20:50:15.528 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: responseHeadersEnd
  2020-09-22 20:50:15.532 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: responseBodyStart
  2020-09-22 20:50:15.534 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: responseBodyEnd
  2020-09-22 20:50:15.547 28144-28277/cn.com.zwwl.bayuwen D/NetworkEventListener: callEnd
  

11.应用实践之案例

• 网络拦截分析，主要是分析网络流量损耗，以及request，respond过程时间。打造网络分析工具……
• 项目代码地址：https://github.com/yangchong211/YCAndroidTool
• 如果你觉得这个拦截网络助手方便了测试，以及开发中查看网络数据，可以star一下……

网络拦截库：https://github.com/yangchong211/YCAndroidTool