diff --git a/spring-hibernate4/src/main/java/org/baeldung/spring/persistence/dao/common/AbstractHibernateDao.java b/spring-hibernate4/src/main/java/org/baeldung/spring/persistence/dao/common/AbstractHibernateDao.java
index 81f6acf9dc..cf293231ab 100644
--- a/spring-hibernate4/src/main/java/org/baeldung/spring/persistence/dao/common/AbstractHibernateDao.java
+++ b/spring-hibernate4/src/main/java/org/baeldung/spring/persistence/dao/common/AbstractHibernateDao.java
@@ -19,7 +19,7 @@ public abstract class AbstractHibernateDao<T extends Serializable> implements IO
     // API
 
     protected final void setClazz(final Class<T> clazzToSet) {
-        clazz = clazzToSet;
+        clazz = Preconditions.checkNotNull(clazzToSet);
     }
 
     @Override
diff --git a/spring-hibernate4/src/main/java/org/baeldung/spring/persistence/service/impl/FooService.java b/spring-hibernate4/src/main/java/org/baeldung/spring/persistence/service/impl/FooService.java
index 6a97596e7d..19223a82ca 100644
--- a/spring-hibernate4/src/main/java/org/baeldung/spring/persistence/service/impl/FooService.java
+++ b/spring-hibernate4/src/main/java/org/baeldung/spring/persistence/service/impl/FooService.java
@@ -7,10 +7,8 @@ import org.baeldung.spring.persistence.service.IFooService;
 import org.baeldung.spring.persistence.service.common.AbstractService;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
-import org.springframework.transaction.annotation.Transactional;
 
 @Service
-@Transactional
 public class FooService extends AbstractService<Foo> implements IFooService {
 
     @Autowired