Make real Test for BO only

src/main/java/fr/eni/demo/bll/ClientServiceImpl.java

@@ -0,0 +1,28 @@
+package fr.eni.demo.bll;
+
+import fr.eni.demo.bo.Client;
+import fr.eni.demo.dal.ClientRepository;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import java.util.Optional;
+
+@Service
+public class ClientServiceImpl implements  ClientService {
+
+  private ClientRepository clientRepository;
+
+  public ClientServiceImpl(ClientRepository clientRepository) {
+    this.clientRepository = clientRepository;
+  }
+
+  @Override
+  public void add(Client client) {
+    clientRepository.save(client);
+  }
+
+  @Override
+  public Optional<Client> findById(Long clientId) {
+    return clientRepository.findById(clientId);
+  }
+}