SimpleTypeHolder considers Object to be a simple type.

spring-data-commons-core/src/main/java/org/springframework/data/mapping/model/SimpleTypeHolder.java

@@ -116,6 +116,9 @@ public class SimpleTypeHolder {
 	 */
 	public boolean isSimpleType(Class<?> type) {
 		Assert.notNull(type);
+		if (Object.class.equals(type)) {
+			return true;
+		}		
 		for (Class<?> clazz : simpleTypes) {
 			if (type == clazz || clazz.isAssignableFrom(type)) {
 				return true;

spring-data-commons-core/src/test/java/org/springframework/data/mapping/SimpleTypeHolderUnitTests.java

@@ -86,4 +86,10 @@ public class SimpleTypeHolderUnitTests {
 		assertThat(second.isSimpleType(SimpleTypeHolder.class), is(true));
 		assertThat(second.isSimpleType(SimpleTypeHolderUnitTests.class), is(true));
 	}
+
+	@Test
+	public void considersObjectToBeSimpleType() {
+		SimpleTypeHolder holder = new SimpleTypeHolder();
+		assertThat(holder.isSimpleType(Object.class), is(true));
+	}
 }