Retrofit2 + OkHttp3设置Http请求头(Headers)方法汇总

在构建网络层时会遇到一个问题就是要手动配置Http请求的Headers，写入缓存Cookie，自定义的User-Agent等参数，但是对于有几十个接口的网络层，我才不想用注解配置Headers，目前网上很多文章的方法真对这两个版本都不是很适用，有的给出的方法已经被删除，有的方法会报出异常
:(

方法一：

在翻阅官方API文档整理后的方法如下：

1.  import okhttp3.Interceptor;

2.  import okhttp3.OkHttpClient;

3.  import okhttp3.Request;

4.  import okhttp3.Response;

5.  import retrofit2.Retrofit;

6.

7.  public class RetrofitAPIManager {

8.

9.      public static final String SERVER_URL = "url";

10.

11.     public static ClientAPI provideClientApi() {

12.         Retrofit retrofit = new Retrofit.Builder()

13.                 .baseUrl(SERVER_URL)

14.                 .client(genericClient())

15.                 .build();

16.         return retrofit.create(ClientAPI.class);

17.     }

18.

19.

20.     public static OkHttpClient genericClient() {

21.         OkHttpClient httpClient = new OkHttpClient.Builder()

22.                 .addInterceptor(new Interceptor() {

23.                     @Override

24.                     public Response intercept(Chain chain) throws IOException {

25.                         Request request = chain.request()

26.                                 .newBuilder()

27.                                 .addHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8")

28.                                 .addHeader("Accept-Encoding", "gzip, deflate")

29.                                 .addHeader("Connection", "keep-alive")

30.                                 .addHeader("Accept", "*/*")

31.                                 .addHeader("Cookie", "add cookies here")

32.                                 .build();

33.                         return chain.proceed(request);

34.                     }

35.

36.                 })

37.                 .build();

38.

39.         return httpClient;

40.     }

41. }

使用Interceptor来拦截并重新设置请求头，测试可用

• List<Interceptor>  interceptors()方法，返回的是一个不可编辑的列表，如果对其进行编辑会报出UnSupportedOperationException
• Interceptor的典型使用场景，就是对request和response的Headers进行编辑

方法二.、

OkHttpClient okHttpClient = new OkHttpClient.Builder()

                .cookieJar(new CookieJar() {

                    private final HashMap<HttpUrl, List<Cookie>> cookieStore = new HashMap<>();

                    @Override

                    public void saveFromResponse(HttpUrl httpUrl, List<Cookie> list) {

                        cookieStore.put(httpUrl, list);

                    }

                    @Override

                    public List<Cookie> loadForRequest(HttpUrl httpUrl) {

                        List<Cookie> cookies = cookieStore.get(httpUrl);

                        return cookies != null ? cookies : new ArrayList<Cookie>();

                    }

                }).build();

方法三、

Request request = new Request.Builder()

                .url(PATH)

                .post(body)

                //取出本地保存的sessionId

                .addHeader("Cookie", "sessionId")

                .build();

        Call call = mOkHttpClient.newCall(request);

        call.enqueue(new Callback() {

            @Override

            public void onFailure(Call call, IOException e) {

            }

            @Override

            public void onResponse(Call call, Response response) throws IOException {

               if (response.isSuccessful()){

                   Headers headers = response.headers();

                   List<String> cookies = headers.values("Set-Cookie");

                   Log.d(TAG, "onResponse: "+cookies.size());

                   for (String str:cookies){

                       if (str.startsWith("PHPSESSID")){

                           //将sessionId保存到本地

                           Log.d(TAG, "onResponse: "+str.split(";")[0]);

                       }

                   }

               }

            }

        });

来自为知笔记(Wiz)