refactor code structure

src/main/java/wtf/beatrice/releasehive/service/AccountService.java

@@ -0,0 +1,17 @@
+package wtf.beatrice.releasehive.service;
+
+import org.hibernate.Session;
+import org.hibernate.Transaction;
+import wtf.beatrice.releasehive.db.HibernateManager;
+import wtf.beatrice.releasehive.model.User;
+
+public class AccountService
+{
+
+    public void registerUser(User user) {
+        Session session = HibernateManager.getSession();
+        Transaction transaction = session.beginTransaction();
+        session.save(user);
+        transaction.commit();
+    }
+}