Merge pull request #30 from jhorstmann/retriever-type-inference

Improve type inference of Retriever

Author: whiskeysierra

src/main/java/org/zalando/riptide/Retriever.java

@@ -37,7 +37,7 @@ public <T> Optional<T> retrieve(final Class<T> type) {
         return retrieve(TypeToken.of(type));
     }
 
-    public <T> Optional<T> retrieve(final TypeToken<?> type) {
+    public <T> Optional<T> retrieve(final TypeToken<T> type) {
         return Optional.ofNullable(captured.getValue())
                 .filter(v -> this.hasRetrieved(type))
                 .map(v -> {

src/test/java/org/example/application/RestIntegrationTest.java

@@ -137,6 +137,26 @@ public void shouldRetrieveParameterizedType() throws IOException {
         assertThat(result.get(0), isA(String.class));
     }
 
+    @Test
+    public void shouldRetrieveParameterizedTypeWithTypeInference() throws IOException {
+        setUp(new PassThroughResponseErrorHandler());
+
+        server.expect(requestTo(url)).andRespond(withSuccess()
+                .contentType(MediaType.APPLICATION_JSON)
+                .body("[\"a\",\"b\"]"));
+
+        final TypeToken<List<String>> typeToken = new TypeToken<List<String>>() {
+        };
+        final List<String> result = unit.execute(GET, url).dispatch(status(),
+                on(OK, typeToken).capture(),
+                anyStatus().call(this::error))
+                .retrieve(typeToken).orElseThrow(() -> new RuntimeException("Unable to retrieve List<String>"));
+
+        assertThat(result, is(not(nullValue())));
+        assertThat(result, hasSize(2));
+        assertThat(result.get(0), isA(String.class));
+    }
+
     @Test
     public void shouldNotRetrieveMappedParameterizedType() throws IOException {
         setUp(new PassThroughResponseErrorHandler());