Okhttp基本使用总结：

引入库：

 implementation 'com.squareup.okhttp3:okhttp:3.2.0'  

okhttp内部封装功能：

final Dispatcher dispatcher;
  final Proxy proxy;
  final List<Protocol> protocols;
  final List<ConnectionSpec> connectionSpecs;
  final List<Interceptor> interceptors;
  final List<Interceptor> networkInterceptors;
  final ProxySelector proxySelector;
  final CookieJar cookieJar;
  final Cache cache;
  final InternalCache internalCache;
  final SocketFactory socketFactory;
  final SSLSocketFactory sslSocketFactory;
  final TrustRootIndex trustRootIndex;
  final HostnameVerifier hostnameVerifier;
  final CertificatePinner certificatePinner;
  final Authenticator proxyAuthenticator;
  final Authenticator authenticator;
  final ConnectionPool connectionPool;
  final Dns dns;
  final boolean followSslRedirects;
  final boolean followRedirects;
  final boolean retryOnConnectionFailure;
  final int connectTimeout;
  final int readTimeout;
  final int writeTimeout;

创建Okhttp对象方式:

        OkHttpClient okHttpClient = new OkHttpClient.Builder()
                .readTimeout(20, TimeUnit.SECONDS)
                .build();

        OkHttpClient okHttpClient1 = new OkHttpClient();

get请求：

OkHttpClient okHttpClient = new OkHttpClient.Builder()
                .readTimeout(20, TimeUnit.SECONDS)
                .build();

        Request request = new Request.Builder()
                .url("")
                .build();
        try {
            Response response = okHttpClient.newCall(request).execute();
            response.body().string();
        } catch (IOException e) {
            e.printStackTrace();
        }

post请求：

       RequestBody requestBody = new FormBody.Builder()
                .add("","")
                .build();

        Request request = new Request.Builder()
                .url("")
                .addHeader("","")
                .post(requestBody)
                .build();

        OkHttpClient okHttpClient = new OkHttpClient.Builder()
                .readTimeout(20, TimeUnit.SECONDS)
                .build();

        try {
            Response response = okHttpClient.newCall(request).execute();
            response.body().string();
        } catch (IOException e) {
            e.printStackTrace();
        }