Change ConnectionDataLoader to use Async loading.

Author: vinayknl

src/main/java/graphql/annotations/dataFetchers/connection/ConnectionDataFetcher.java

@@ -21,10 +21,12 @@
 import java.lang.reflect.Constructor;
 import java.util.Arrays;
 import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
 
 import static graphql.annotations.processor.util.ReflectionKit.constructNewInstance;
+import static java.util.concurrent.CompletableFuture.supplyAsync;
 
-public class ConnectionDataFetcher<T> implements DataFetcher<graphql.relay.Connection<T>> {
+public class ConnectionDataFetcher<T> implements DataFetcher<CompletableFuture<graphql.relay.Connection<T>>> {
     private final DataFetcher<?> actualDataFetcher;
     private final Constructor<ConnectionFetcher<T>> constructor;
 
@@ -44,8 +46,8 @@ public ConnectionDataFetcher(Class<? extends ConnectionFetcher<T>> connection, D
     }
 
     @Override
-    public graphql.relay.Connection<T> get(DataFetchingEnvironment environment) {
+    public CompletableFuture<graphql.relay.Connection<T>> get(DataFetchingEnvironment environment) {
         ConnectionFetcher<T> conn = constructNewInstance(constructor, actualDataFetcher);
-        return conn.get(environment);
+        return supplyAsync(() -> conn.get(environment));
     }
 }