From 7ac97bfeae5e7e9debe748198a90f53649729081 Mon Sep 17 00:00:00 2001
From: Oliver Gierke <ogierke@gopivotal.com>
Date: Thu, 13 Feb 2014 12:06:26 +0100
Subject: [PATCH] DATACMNS-440 - Fixed map value type resolving for Map value
 types.

Previously the map value type resolving algorithm checked the value type to be of type Map again to shortcut the resolution. We now weakened this to an assignment check and eagerly resolve the generic type if its bound on exactly that level already. If no concrete type argument can be found, we fall back to the general generics resolution mechanism.
---
 .../util/ParameterizedTypeInformation.java    |  8 ++++--
 .../util/ClassTypeInformationUnitTests.java   | 26 +++++++++++++++++++
 2 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/src/main/java/org/springframework/data/util/ParameterizedTypeInformation.java b/src/main/java/org/springframework/data/util/ParameterizedTypeInformation.java
index 1d11fa7300..09ecc8ae1a 100644
--- a/src/main/java/org/springframework/data/util/ParameterizedTypeInformation.java
+++ b/src/main/java/org/springframework/data/util/ParameterizedTypeInformation.java
@@ -55,9 +55,13 @@ public ParameterizedTypeInformation(ParameterizedType type, TypeDiscoverer<?> pa
 	@Override
 	public TypeInformation<?> getMapValueType() {
 
-		if (Map.class.equals(getType())) {
+		if (Map.class.isAssignableFrom(getType())) {
+
 			Type[] arguments = type.getActualTypeArguments();
-			return createInfo(arguments[1]);
+
+			if (arguments.length > 1) {
+				return createInfo(arguments[1]);
+			}
 		}
 
 		Class<?> rawType = getType();
diff --git a/src/test/java/org/springframework/data/util/ClassTypeInformationUnitTests.java b/src/test/java/org/springframework/data/util/ClassTypeInformationUnitTests.java
index 71b6e26686..edae81bd5b 100644
--- a/src/test/java/org/springframework/data/util/ClassTypeInformationUnitTests.java
+++ b/src/test/java/org/springframework/data/util/ClassTypeInformationUnitTests.java
@@ -25,6 +25,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.SortedMap;
 
 import org.junit.Test;
 import org.springframework.data.mapping.Person;
@@ -295,6 +296,26 @@ public void returnsNullForRawTypesOnly() {
 		assertThat(from(MyIterable.class).getComponentType(), is(notNullValue()));
 	}
 
+	/**
+	 * @see DATACMNS-440
+	 */
+	@Test
+	public void detectsSpecialMapAsMapValueType() {
+
+		TypeInformation<SuperGenerics> information = ClassTypeInformation.from(SuperGenerics.class);
+
+		TypeInformation<?> propertyInformation = information.getProperty("seriously");
+		assertThat(propertyInformation.getType(), is((Object) SortedMap.class));
+
+		TypeInformation<?> mapValueType = propertyInformation.getMapValueType();
+		assertThat(mapValueType.getType(), is((Object) SortedMap.class));
+		assertThat(mapValueType.getComponentType().getType(), is((Object) String.class));
+
+		TypeInformation<?> nestedValueType = mapValueType.getMapValueType();
+		assertThat(nestedValueType.getType(), is((Object) List.class));
+		assertThat(nestedValueType.getComponentType().getType(), is((Object) Person.class));
+	}
+
 	static class StringMapContainer extends MapContainer<String> {
 
 	}
@@ -424,4 +445,9 @@ interface Identifiable {
 	interface MyRawIterable extends Iterable {}
 
 	interface MyIterable<T> extends Iterable<T> {}
+
+	static class SuperGenerics {
+
+		SortedMap<String, ? extends SortedMap<String, List<Person>>> seriously;
+	}
 }