Use full type information for identifier and domain types exposed byRepositoryMetadata.

See #2518.

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

@@ -53,6 +53,7 @@ import org.springframework.util.ReflectionUtils;
  * @author Christoph Strobl
  * @author Mark Paluch
  * @author Jürgen Diez
+ * @author Alessandro Nistico
  */
 class TypeDiscoverer<S> implements TypeInformation<S> {
 
@@ -293,6 +294,16 @@ class TypeDiscoverer<S> implements TypeInformation<S> {
 	public Class<S> getType() {
 		return resolvedType.get();
 	}
+	
+	@Override
+	public Type getGenericType() {
+		return type;
+	}
+
+	@Override
+	public TypeInformation<?> getGenericTypeInformation() {
+		return createInfo(type);
+	}
 
 	@Override
 	public ClassTypeInformation<?> getRawTypeInformation() {

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

@@ -17,6 +17,7 @@ package org.springframework.data.util;
 
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Method;
+import java.lang.reflect.Type;
 import java.util.List;
 
 import org.springframework.lang.Nullable;
@@ -27,6 +28,7 @@ import org.springframework.lang.Nullable;
  *
  * @author Oliver Gierke
  * @author Mark Paluch
+ * @author Alessandro Nistico
  */
 public interface TypeInformation<S> {
 
@@ -148,6 +150,15 @@ public interface TypeInformation<S> {
 	 * @return
 	 */
 	Class<S> getType();
+	
+	/**
+	 * Returns the type of the property with all resolvable generics applied
+	 *
+	 * @return
+	 */
+	default Type getGenericType() {
+		return getType();
+	}
 
 	/**
 	 * Returns the user type of the property if proxied.
@@ -170,6 +181,13 @@ public interface TypeInformation<S> {
 	 */
 	ClassTypeInformation<?> getRawTypeInformation();
 
+	/**
+	 * Returns a {@link TypeInformation} to represent the {@link TypeInformation} of the type of the current instance with all the generics parameters resolved.
+	 *
+	 * @return
+	 */
+	TypeInformation<?> getGenericTypeInformation();
+
 	/**
 	 * Transparently returns the {@link java.util.Map} value type if the type is a {@link java.util.Map}, returns the
 	 * component type if the type {@link #isCollectionLike()} or the simple type if none of this applies.

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

@@ -28,6 +28,7 @@ import org.springframework.util.Assert;
  * {@link TypeVariable} is being used in.
  *
  * @author Oliver Gierke
+ * @author Alessandro Nistico
  */
 class TypeVariableTypeInformation<T> extends ParentTypeAwareTypeInformation<T> {
 
@@ -49,6 +50,11 @@ class TypeVariableTypeInformation<T> extends ParentTypeAwareTypeInformation<T> {
 
 		this.variable = variable;
 	}
+	
+	@Override
+	public TypeInformation<?> getGenericTypeInformation() {
+		return createInfo(getTypeVariableMap().getOrDefault(variable, Object.class));
+	}
 
 	@Override
 	public boolean equals(@Nullable Object obj) {