From 979859c6ae98d62eda793513f1e0e0d33724972f Mon Sep 17 00:00:00 2001
From: zentol <s.motsu@web.de>
Date: Mon, 10 Nov 2014 14:12:28 +0100
Subject: [PATCH] [FLINK-1227] KeySelector can now extend ResultTypeQueryable

---
 .../org/apache/flink/api/java/typeutils/TypeExtractor.java     | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/flink-java/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java b/flink-java/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java
index 7dcaa0f7ebaf2..9140d41f743df 100644
--- a/flink-java/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java
+++ b/flink-java/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java
@@ -112,6 +112,9 @@ public static <IN1, IN2, OUT> TypeInformation<OUT> getCrossReturnTypes(CrossFunc
 	}
 	
 	public static <IN, OUT> TypeInformation<OUT> getKeySelectorTypes(KeySelector<IN, OUT> selectorInterface, TypeInformation<IN> inType) {
+		if(selectorInterface instanceof ResultTypeQueryable) {
+			return ((ResultTypeQueryable<OUT>) selectorInterface).getProducedType();
+		}
 		return getUnaryOperatorReturnType((Function) selectorInterface, KeySelector.class, false, false, inType);
 	}