Retrofit是Square開發(fā)的一個用于網(wǎng)絡(luò)請求的開源庫，其實就是對okhttp進行更進一步封裝娩嚼。

retrofit在gradle中的配置:

    compile 'io.reactivex.rxjava2:rxjava:2.0.1'
    compile 'io.reactivex.rxjava2:rxandroid:2.0.1'//我這里還使用了rxjava
  compile 'com.squareup.retrofit2:retrofit:2.1.0'
    compile 'com.squareup.retrofit2:converter-gson:2.1.0'
    compile 'com.jakewharton.retrofit:retrofit2-rxjava2-adapter:1.0.0'
    compile 'com.squareup.okhttp3:okhttp:3.4.1'
    compile 'com.squareup.okhttp3:logging-interceptor:3.4.1'

保存cookie和同步cookie攔截器咨堤，等會初始化retrofit用到:

/**
 * 保存cookie和同步cookie攔截器
 * Created by Administrator on 2017/9/5.
 */

class GetCookiesInterceptor implements Interceptor {
    private Context context;
    public static final String SP_NAME = "SharedPreferencesName";

    GetCookiesInterceptor(Context context) {
        super();
        this.context = context;
    }

    @Override
    public Response intercept(Chain chain) throws IOException {
        Request.Builder builder = chain.request().newBuilder();
        SharedPreferences mSharedPreferences=context.getSharedPreferences(SP_NAME, Context.MODE_PRIVATE);
        String str = mSharedPreferences.getString(key, null)
        if (StringUtils.isNotEmpty(str)) {
            Type type = new TypeToken<List<String>>() {
            }.getType();
            List<String> list = new Gson().fromJson(str, type);
            for (String s : list) {
                L.d(s);
                builder.addHeader("cookie", s);//統(tǒng)一添加這里有多少就傳多少（多cookie）
            }
        }
        Response response = chain.proceed(builder.build());
        List<String> cookie = response.headers("Set-Cookie");
        if (!cookie.isEmpty()) {//保存cookie
            SharedPreferences mSharedPreferences=context.getSharedPreferences(SP_NAME, Context.MODE_PRIVATE);
            mSharedPreferences.edit().putString(Contact.COOKIE, new Gson().toJson(cookie)).apply();
        }
        return response;
    }

}

自定義轉(zhuǎn)換器：

/**
 * 自定義轉(zhuǎn)換器
 * Add myConverter factory for serialization and deserialization of objects.
 * Created by Administrator on 2017/9/5.
 */

public class MGsonConverterFactory extends Converter.Factory {
    private boolean isAes;
    private Gson gson;

    public static MGsonConverterFactory create(boolean isAes) {
        return new MGsonConverterFactory(isAes);
    }


    private MGsonConverterFactory(boolean isAes) {
        this.isAes = isAes;
        gson = new Gson();
    }

    @Override
    public Converter<?, RequestBody> requestBodyConverter(Type type, Annotation[] parameterAnnotations, Annotation[] methodAnnotations, Retrofit retrofit) {
        return new RequestBodyConverter<>(isAes, gson);
    }

    @Override
    public Converter<ResponseBody, ?> responseBodyConverter(Type type, Annotation[] annotations, Retrofit retrofit) {
        return new ResponseBodyConverter<>(type, isAes);
    }


    /**
     * 自定義請求RequestBody
     */
    public static class RequestBodyConverter<T> implements Converter<T, RequestBody> {
        private static final MediaType MEDIA_TYPE = MediaType.parse("application/wxt;charset=UTF-8");
        private static final MediaType MEDIA_TYPE1 = MediaType.parse("application/json;charset=UTF-8");
        private boolean isAes;
        private Gson gson;


        public RequestBodyConverter(boolean isAes, Gson gson) {
            this.isAes = isAes;
            this.gson = gson;
        }

        @Override
        public RequestBody convert(T value) throws IOException {//T就是傳入的參數(shù)
            if (isAes) {//這里加上你自己的加密處理
                AES aes = new AES();
                return RequestBody.create(MEDIA_TYPE, aes.encrypt(gson.toJson(value).getBytes()));
            } else {
                return RequestBody.create(MEDIA_TYPE1, gson.toJson(value));
            }
        }

    }

    /**
     * 自定義響應(yīng)ResponseBody
     */
    public class ResponseBodyConverter<T> implements Converter<ResponseBody, T> {
        private boolean isAes;
        private Type type;

        public ResponseBodyConverter(Type type, boolean isAes) {
            this.isAes = isAes;
            this.type = type;
        }

        /**
         * @param value
         * @return T
         * @throws IOException
         */
        @Override
        public T convert(ResponseBody value) throws IOException {
            try {
                if (isAes) {////這里加上你自己的解密方法
                    byte[] b = value.bytes();
                    AES aes = new AES();
                    byte[] a = aes.decrypt(b);
                    String json = new String(a);
                    return new Gson().fromJson(json, type);
                } else {
                    String json = value.string();
                    return new Gson().fromJson(json, type);
                }
            } finally {
                value.close();
            }
        }

    }
}

接下來我們就初始化retrofit：

/**
 * 提供Retrofit
 * Created by Administrator on 2017/9/5.
 */

public class RetrofitProvider {
    private static final String BASE_URL = "";//寫上你的baseurl

    public static Retrofit create(Context context, boolean isAes) {//第二個參數(shù)是否加密
        OkHttpClient.Builder builder = new OkHttpClient().newBuilder();
        builder.readTimeout(90, TimeUnit.SECONDS);
        builder.connectTimeout(90, TimeUnit.SECONDS);
        if (BuildConfig.DEBUG) {//打印請求日志
            HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
            interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
            builder.addInterceptor(interceptor);
        }
        builder.addInterceptor(new GetCookiesInterceptor(context));//攔截器维蒙，用于保存cookie和添加統(tǒng)一求情頭
        return new Retrofit.Builder().baseUrl(BASE_URL)
                .client(builder.build())
                .addConverterFactory(MGsonConverterFactory.create(isAes))//加入剛剛自定義的轉(zhuǎn)換器MGsonConverterFactory 
                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                .build();
    }

    public static Retrofit create(Context context) {//默認不加密
        return create(context, false);
    }
}

前期工作準備好了哪廓，我們就開始看看如何使用吧为肮！
1.結(jié)合rejava使用，編寫API :

public interface ApiService {

    @POST("/user/getUser.action")
    Observable<UserEntity> getUsers(@Body Map<String, String> map);

}

  private void getUser() {
        Retrofit retrofit = RetrofitProvider.create(this, true);
        ApiService apiService = retrofit.create(ApiService.class);
        Map<String, String> map = new HashMap<>();
        map.put("userName", "userName");
        map.put("password", "123456");
        apiService.getUsers(map).subscribeOn(Schedulers.io()) 
                .observeOn(AndroidSchedulers.mainThread())  
                .subscribe(new Consumer<UserEntity >() {
                    @Override
                    public void accept(UserEntity user) throws Exception {
                        Toast.makeText(MainActivity.this, "獲取成功", Toast.LENGTH_SHORT).show();
                    }
                }, new Consumer<Throwable>() {
                    @Override
                    public void accept(Throwable throwable) throws Exception {
                        Toast.makeText(MainActivity.this, "獲取失敗", Toast.LENGTH_SHORT).show();
                    }
                });
    }

單獨使用：

public interface ApiService {

    @POST("/user/getUser.action")
    Call<UserEntity > getUser(@Body Map<String, String> map);

}

 private void getUser() {
        Retrofit retrofit = RetrofitProvider.create(this, true);
        ApiService apiService = retrofit.create(ApiService.class);
        Map<String, String> map = new HashMap<String, String>();
        map.put("userName", "username");
        map.put("password", "123456");
        Call<UserEntity > call = apiService.getUser(map);
        call.enqueue(new Callback<UserEntity >() {
            @Override
            public void onResponse(Call<UserEntity > call, Response<UserEntity > response) {
                L.d(response.body().toString());
            }

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

            }
        });
    }