先新增依賴：
compile ‘com.squareup.retrofit2:retrofit:2.1.0’
compile ‘com.squareup.retrofit2:converter-gson:2.1.0’
compile ‘com.squareup.okhttp3:logging-interceptor:3.1.2’

二：okhttp已經為我們提供了一個Interceptor的實現類：HttpLoggingInterceptor。只要稍作設定就可以：

 HttpLoggingInterceptor logging = new HttpLoggingInterceptor(new HttpLoggingInterceptor.Logger
 
() {
            @Override public void log(String message) {
//                Timber.tag("OkHttp").d(message);
//                Logger.e("okhttp",message);
                Log.e("okhttp",message);
            }
        });
        logging.setLevel(HttpLoggingInterceptor.Level.BODY);//Level中還有其他等級
        OkHttpClient client = new OkHttpClient.Builder
 
()
                .addInterceptor(logging)
                .build();

三：使用

 Retrofit retrofit = new Retrofit.Builder()
                .baseUrl("https://api.douban.com/v2/")
                .addConverterFactory(GsonConverterFactory.create(new GsonBuilder().create()))
                .client(client)//新增上面設定好的OkHttpClient
                .build
 
();

下面是請求的程式碼：

 RetrofitService service = retrofit.create(RetrofitService.class);
        Call<Book> call =  service.getSearchBook("金瓶梅", null, 0, 1);

        call.enqueue(new Callback<Book>() {
            @Override
            public void onResponse(Call<Book> call, Response<Book> response) {
                button.setText(response.body()+"");
//                Log.e("Json",""+response.body().toString());
            }
            @Override
            public void onFailure(Call<Book> call, Throwable t) {
            }
        });

接下我們檢視日誌：