HttpOutputMessageAsyncClientHttpRequestAdapter implements AsyncClientHttpRequest { @Nonnull @Override public ListenableFuture<ClientHttpResponse> executeAsync() { throw new UnsupportedOperationException(); }  @Nonnull @Override ListenableFuture<ClientHttpResponse> executeAsync(); @Nonnull // TODO(Spring 5): @Override String getMethodValue(); HttpMethod getMethod(); @Nonnull @Override URI getURI();  }
@Test void executeAsync() { assertThrows(UnsupportedOperationException.class, unit::executeAsync); }