diff --git a/src/test/java/org/gcube/informationsystem/resourceregistry/schema/SchemaManagementImplTest.java b/src/test/java/org/gcube/informationsystem/resourceregistry/schema/SchemaManagementImplTest.java
index abb9f9a..142b75f 100644
--- a/src/test/java/org/gcube/informationsystem/resourceregistry/schema/SchemaManagementImplTest.java
+++ b/src/test/java/org/gcube/informationsystem/resourceregistry/schema/SchemaManagementImplTest.java
@@ -5,6 +5,7 @@ package org.gcube.informationsystem.resourceregistry.schema;
 
 import java.util.List;
 
+import org.gcube.informationsystem.model.ISManageable;
 import org.gcube.informationsystem.model.embedded.Embedded;
 import org.gcube.informationsystem.model.embedded.Header;
 import org.gcube.informationsystem.model.entity.Entity;
@@ -35,7 +36,7 @@ public class SchemaManagementImplTest {
 
 	@Test
 	public void registerEmbeddedTypeSchema() throws Exception {
-		Class<?> clz = Header.class;
+		Class<? extends Embedded> clz = Header.class;
 		String json = TypeBinder.serializeType(clz);
 		logger.debug(json);
 		//new SchemaManagementImpl().create(json, AccessType.EMBEDDED);
@@ -49,7 +50,7 @@ public class SchemaManagementImplTest {
 
 	@Test
 	public void registerFacetSchema() throws Exception {
-		Class<?> clz = ContactFacet.class;
+		Class<? extends Facet> clz = ContactFacet.class;
 		String json = TypeBinder.serializeType(clz);
 		TypeBinder.deserializeTypeDefinition(json);
 	}
@@ -65,7 +66,7 @@ public class SchemaManagementImplTest {
 
 	@Test
 	public void registerEntityTypeSchema() throws Exception {
-		Class<?> clz = Entity.class;
+		Class<? extends Entity> clz = Entity.class;
 		String json = TypeBinder.serializeType(clz);
 		logger.trace(json);
 		// new SchemaManagementImpl().registerEntitySchema(json);
@@ -73,7 +74,7 @@ public class SchemaManagementImplTest {
 
 	@Test
 	public void registerResourceSchema() throws Exception {
-		Class<?> clz = Resource.class;
+		Class<? extends Resource> clz = Resource.class;
 		String json = TypeBinder.serializeType(clz);
 		logger.info(json);
 		// new SchemaManagementImpl().registerFacetSchema(json);
@@ -87,7 +88,7 @@ public class SchemaManagementImplTest {
 
 	@Test
 	public void registerRelation() throws Exception {
-		Class<?> clz = Hosts.class;
+		Class<? extends ISManageable> clz = Hosts.class;
 		String json = TypeBinder.serializeType(clz);
 		logger.trace(json);
 		// new SchemaManagementImpl().registerFacetSchema(json);