Retrofit 注解对应Http请求报文

@Get

    @GET("path")
    Call<String> get();


      GET /path HTTP/1.1
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

@Post

    @POST("path")
    Call<String> post();


      POST /path HTTP/1.1
      Content-Length: 0
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

@Path

    @POST("path/{path}")
    Call<String> path(@Path("path") String path);

      POST /path/path_value HTTP/1.1
      Content-Length: 0
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

@Header

    @GET("path")
    Call<String> head(@Header("header_key")String header_value);

      GET /path HTTP/1.1
      header_key: header_value
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

@Query

    @GET("path")
    Call<String> query(@Query("query")String query);


      GET /path?query=query_value HTTP/1.1
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

@QueryMap

    @GET("path")
    Call<String> queryMap(@QueryMap Map<String,String> map);


      GET /path?query_key=query_value HTTP/1.1
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

@Field

    @FormUrlEncoded
    @POST("path")
    Call<String> formUrlEncoded_filed(@Field("filed")String filed);



      POST /path HTTP/1.1
      Content-Type: application/x-www-form-urlencoded
      Content-Length: 17
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

      filed=filed_value

@Part##

    @Multipart
    @POST("path")
    Call<String> part(@Part("part") String part);


      POST /path HTTP/1.1
      Content-Type: multipart/form-data; boundary=c15df5c5-4a97-43b4-acae-998e3a89a075
      Content-Length: 245
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

      --c15df5c5-4a97-43b4-acae-998e3a89a075
      Content-Disposition: form-data; name="part"
      Content-Transfer-Encoding: binary
      Content-Type: application/json; charset=UTF-8
      Content-Length: 12

      "part_value"
      --c15df5c5-4a97-43b4-acae-998e3a89a075--

@Body

    @POST("path")
    Call<String> body(@Body User body);

      POST /path HTTP/1.1
      Content-Type: application/json; charset=UTF-8
      Content-Length: 27
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

      {"age":25,"username":"dog"}

为什么要搞这个##

因为在使用 @Part 提交表单的时候遇到了一个问题。

请问为什么Retrofit以Mutipart上传参数时，String参数会多一对双引号

丶贰九

在Post请求中,@Part注解默认的Content-Type类型是“application/json”，

怪盗kidou

造成的主要原因有两个：

• 1、retrofit并不内置String的Converter，只有在Url、Header、普通表单字段相关的注解才会默认处理成String。
• 2、你注册了GsonConverter，而GsonConverter是不会判断能不能处理该类型的，全部转成json，而String在json里就是 "String"的形式，所以长度变成5,Content-Type头是application/json; charset=UTF-8

解决方法

retrofit = new Retrofit.Builder()
               .baseUrl("http://www.baidu.com/")
//                .addConverterFactory(GsonConverterFactory.create())
               .client(client)
               .addConverterFactory(ScalarsConverterFactory.create())
               .addConverterFactory(GsonConverterFactory.create())
               .build();

我终于知道为什么以前看的框架会添加两个ConverterFactory并不是作者瞎搞，而是我一无所知。。 也就是在GsonConverterFactory.create()之前，添加一个ScalarsConverterFactory.create() 这样，使用@Part请求的报文的Content-Type就不会是application/json

    @Multipart
    @POST("path")
    Call<String> part(@Part("part") String part);

            
      POST /path HTTP/1.1
      Content-Type: multipart/form-data; boundary=36f57677-f08c-4a5f-8000-104fa606d580
      Content-Length: 237
      Host: www.baidu.com
      Connection: Keep-Alive
      Accept-Encoding: gzip
      User-Agent: okhttp/3.9.1

      --36f57677-f08c-4a5f-8000-104fa606d580
      Content-Disposition: form-data; name="part"
      Content-Transfer-Encoding: binary
      Content-Type: text/plain; charset=UTF-8
      Content-Length: 10

      part_value
      --36f57677-f08c-4a5f-8000-104fa606d580--