DATACMNS-485 - Fixed bug in ParameterizedTypeInformation.hashCode().

Previously, ParameterizedTypeInformation.hashCode() had been inconsistent to equals in case of a fully resolved parameterized type. This is now fixed by not including the parent reference in case a parameterized type is resolved completely.

Also, TypeDiscoverer.getActualType() does not return the component type for non-collection/non-maps anymore to make sure we don't accidentally unwrap parameterized types.

Author: odrotbohm

src/main/java/org/springframework/data/util/ParameterizedTypeInformation.java

@@ -181,7 +181,7 @@ public boolean equals(Object obj) {
 	 */
 	@Override
 	public int hashCode() {
-		return super.hashCode() + (isResolvedCompletely() ? this.type.hashCode() : 0);
+		return isResolvedCompletely() ? this.type.hashCode() : super.hashCode();
 	}
 
 	/* 

src/main/java/org/springframework/data/util/TypeDiscoverer.java

@@ -284,13 +284,7 @@ public TypeInformation<?> getActualType() {
 			return getComponentType();
 		}
 
-		List<TypeInformation<?>> arguments = getTypeArguments();
-
-		if (arguments.isEmpty()) {
-			return this;
-		}
-
-		return arguments.get(arguments.size() - 1);
+		return this;
 	}
 
 	/*

src/test/java/org/springframework/data/util/ParameterizedTypeUnitTests.java

@@ -95,6 +95,31 @@ public void createsToStringRepresentation() {
 				is("org.springframework.data.util.ParameterizedTypeUnitTests$Localized<java.lang.String>"));
 	}
 
+	/**
+	 * @see DATACMNS-485
+	 */
+	@Test
+	@SuppressWarnings("rawtypes")
+	public void hashCodeShouldBeConsistentWithEqualsForResolvedTypes() {
+
+		TypeInformation first = from(First.class).getProperty("property");
+		TypeInformation second = from(Second.class).getProperty("property");
+
+		assertThat(first, is(second));
+		assertThat(first.hashCode(), is(second.hashCode()));
+	}
+
+	/**
+	 * @see DATACMNS-485
+	 */
+	@Test
+	@SuppressWarnings("rawtypes")
+	public void getActualTypeShouldNotUnwrapParameterizedTypes() {
+
+		TypeInformation type = from(First.class).getProperty("property");
+		assertThat(type.getActualType(), is(type));
+	}
+
 	@SuppressWarnings("serial")
 	class Localized<S> extends HashMap<Locale, S> {
 		S value;
@@ -109,4 +134,16 @@ class Foo {
 		Localized<String> param;
 		Localized2<String> param2;
 	}
+
+	class Parameterized<T> {
+		T property;
+	}
+
+	class First {
+		Parameterized<String> property;
+	}
+
+	class Second {
+		Parameterized<String> property;
+	}
 }