Add AnnotatedConverterFactory sample

samples/pom.xml

@@ -24,6 +24,11 @@
       <artifactId>retrofit-mock</artifactId>
       <version>${project.version}</version>
     </dependency>
+    <dependency>
+      <groupId>${project.groupId}</groupId>
+      <artifactId>converter-moshi</artifactId>
+      <version>${project.version}</version>
+    </dependency>
     <dependency>
       <groupId>${project.groupId}</groupId>
       <artifactId>converter-gson</artifactId>

samples/src/main/java/com/example/retrofit/AnnotatedConverters.java

@@ -0,0 +1,155 @@
+/*
+ * Copyright (C) 2017 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.example.retrofit;
+
+import com.google.gson.GsonBuilder;
+import java.io.IOException;
+import java.lang.annotation.Annotation;
+import java.lang.annotation.Retention;
+import java.lang.reflect.Type;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import okhttp3.RequestBody;
+import okhttp3.ResponseBody;
+import okhttp3.mockwebserver.MockResponse;
+import okhttp3.mockwebserver.MockWebServer;
+import org.simpleframework.xml.Attribute;
+import org.simpleframework.xml.Default;
+import org.simpleframework.xml.DefaultType;
+import retrofit2.Call;
+import retrofit2.Converter;
+import retrofit2.Retrofit;
+import retrofit2.converter.gson.GsonConverterFactory;
+import retrofit2.converter.moshi.MoshiConverterFactory;
+import retrofit2.converter.simplexml.SimpleXmlConverterFactory;
+import retrofit2.http.GET;
+
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
+final class AnnotatedConverters {
+  public static final class AnnotatedConverterFactory extends Converter.Factory {
+    private final Map<Class<? extends Annotation>, Converter.Factory> factories;
+
+    public static final class Builder {
+      private final Map<Class<? extends Annotation>, Converter.Factory> factories =
+          new LinkedHashMap<>();
+
+      public Builder add(Class<? extends Annotation> cls, Converter.Factory factory) {
+        if (cls == null) {
+          throw new NullPointerException("cls == null");
+        }
+        if (factory == null) {
+          throw new NullPointerException("factory == null");
+        }
+        factories.put(cls, factory);
+        return this;
+      }
+
+      public AnnotatedConverterFactory build() {
+        return new AnnotatedConverterFactory(factories);
+      }
+    }
+
+    AnnotatedConverterFactory(Map<Class<? extends Annotation>, Converter.Factory> factories) {
+      this.factories = new LinkedHashMap<>(factories);
+    }
+
+    @Override
+    public Converter<ResponseBody, ?> responseBodyConverter(Type type, Annotation[] annotations,
+        Retrofit retrofit) {
+      for (Annotation annotation : annotations) {
+        Converter.Factory factory = factories.get(annotation.annotationType());
+        if (factory != null) {
+          return factory.responseBodyConverter(type, annotations, retrofit);
+        }
+      }
+      return null;
+    }
+
+    @Override public Converter<?, RequestBody> requestBodyConverter(Type type,
+        Annotation[] parameterAnnotations, Annotation[] methodAnnotations, Retrofit retrofit) {
+      for (Annotation annotation : parameterAnnotations) {
+        Converter.Factory factory = factories.get(annotation.annotationType());
+        if (factory != null) {
+          return factory.requestBodyConverter(type, parameterAnnotations, methodAnnotations,
+              retrofit);
+        }
+      }
+      return null;
+    }
+  }
+
+  @Retention(RUNTIME) public @interface Moshi {
+  }
+
+  @Retention(RUNTIME) public @interface Gson {
+  }
+
+  @Retention(RUNTIME) public @interface SimpleXml {
+  }
+
+  @Default(value = DefaultType.FIELD) static final class Library {
+    @Attribute String name;
+  }
+
+  interface Service {
+    @GET("/") @Moshi Call<Library> exampleMoshi();
+
+    @GET("/") @Gson Call<Library> exampleGson();
+
+    @GET("/") @SimpleXml Call<Library> exampleSimpleXml();
+
+    @GET("/") Call<Library> exampleDefault();
+  }
+
+  public static void main(String... args) throws IOException {
+    MockWebServer server = new MockWebServer();
+    server.start();
+    server.enqueue(new MockResponse().setBody("{\"name\": \"Moshi\"}"));
+    server.enqueue(new MockResponse().setBody("{\"name\": \"Gson\"}"));
+    server.enqueue(new MockResponse().setBody("<user name=\"SimpleXML\"/>"));
+    server.enqueue(new MockResponse().setBody("{\"name\": \"Gson\"}"));
+
+    com.squareup.moshi.Moshi moshi = new com.squareup.moshi.Moshi.Builder().build();
+    com.google.gson.Gson gson = new GsonBuilder().create();
+    MoshiConverterFactory moshiConverterFactory = MoshiConverterFactory.create(moshi);
+    GsonConverterFactory gsonConverterFactory = GsonConverterFactory.create(gson);
+    SimpleXmlConverterFactory simpleXmlConverterFactory = SimpleXmlConverterFactory.create();
+    Retrofit retrofit = new Retrofit.Builder().baseUrl(server.url("/"))
+        .addConverterFactory(
+            new AnnotatedConverterFactory.Builder().add(Moshi.class, moshiConverterFactory)
+                .add(Gson.class, gsonConverterFactory)
+                .add(SimpleXml.class, simpleXmlConverterFactory)
+                .build())
+        .addConverterFactory(gsonConverterFactory)
+        .build();
+    Service service = retrofit.create(Service.class);
+
+    Library library1 = service.exampleMoshi().execute().body();
+    System.out.println("Library 1: " + library1.name);
+
+    Library library2 = service.exampleGson().execute().body();
+    System.out.println("Library 2: " + library2.name);
+
+    Library library3 = service.exampleSimpleXml().execute().body();
+    System.out.println("Library 3: " + library3.name);
+
+    Library library4 = service.exampleDefault().execute().body();
+    System.out.println("Library 4: " + library4.name);
+
+    server.shutdown();
+  }
+}