add test for custom user details service

spring-userservice/src/main/java/org/baeldung/user/dao/MyUserDAO.java

@@ -29,6 +29,12 @@ public class MyUserDAO {
         entityManager.persist(user);
         return user;
     }
+    
+    public void removeUserByUsername(String username) {
+        final Query query = entityManager.createQuery("delete from MyUser where username=:username");
+        query.setParameter("username", username);
+        query.executeUpdate();
+    }
 
     public EntityManager getEntityManager() {
         return entityManager;

spring-userservice/src/main/java/org/baeldung/user/service/MyUserService.java

@@ -1,5 +1,8 @@
 package org.baeldung.user.service;
 
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+
 import org.baeldung.persistence.model.MyUser;
 import org.baeldung.user.dao.MyUserDAO;
 import org.baeldung.web.MyUserDto;
@@ -14,6 +17,9 @@ public class MyUserService {
 
     @Autowired
     private PasswordEncoder passwordEncoder;
+    
+    @PersistenceContext
+    private EntityManager entityManager;
 
     @Autowired
     MyUserDAO myUserDAO;
@@ -33,6 +39,10 @@ public class MyUserService {
         final MyUser user = myUserDAO.findByUsername(username);
         return user;
     }
+    
+    public void removeUserByUsername(String username){
+        myUserDAO.removeUserByUsername(username);
+    }
 
     private boolean usernameExists(final String username) {
         final MyUser user = myUserDAO.findByUsername(username);