Questions tagged [retrofit2]

To use it with Maven:

<dependency>
  <groupId>com.squareup.retrofit2</groupId>
  <artifactId>retrofit</artifactId>
  <version>2.3.0</version>
</dependency>

Or with Gradle:

compile 'com.squareup.retrofit2:retrofit:2.X.X'

It requires minimum Android 2.3 (Gingerbread) and Java 7 to use it.

If you are using ProGuard add following options:

# Retain generic type information for use by reflection by converters and adapters.
-keepattributes Signature
# Retain service method parameters.
-keepclassmembernames,allowobfuscation interface * {
    @retrofit2.http.* <methods>;
}
# Ignore annotation used for build tooling.
-dontwarn org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement

How to use it:

Retrofit turns your HTTP API into a Java interface.

public interface GitHubService {
  @GET("users/{user}/repos")
  Call<List<Repo>> listRepos(@Path("user") String user);
}

This Retrofit class generates an implementation of the GitHubService interface.

Retrofit retrofit = new Retrofit.Builder()
    .baseUrl("https://api.github.com/")
    .build();

GitHubService service = retrofit.create(GitHubService.class);

Each call from the created GitHubService can make a synchronous or asynchronous HTTP request to the remote web server.

Call<List<Repo>> repos = service.listRepos("octocat");

Use annotations to describe the HTTP request:

• URL parameter replacement and query parameter support
• Object conversion to request body (e.g., JSON, protocol buffers)
• Multipart request body and file upload