diff --git a/messaging/src/test/java/messagebroker/handlers/AddHandlerMessageHandlerTest.java b/messaging/src/test/java/messagebroker/handlers/AddHandlerMessageHandlerTest.java
index f93381a..8a7a713 100644
--- a/messaging/src/test/java/messagebroker/handlers/AddHandlerMessageHandlerTest.java
+++ b/messaging/src/test/java/messagebroker/handlers/AddHandlerMessageHandlerTest.java
@@ -5,6 +5,8 @@ import messagebroker.MessageHandlerContext;
 import messagebroker.UnknownMessageFormatException;
 import org.junit.Test;
 
+import java.io.OutputStream;
+
 import static org.mockito.Mockito.*;
 
 public class AddHandlerMessageHandlerTest {
@@ -19,6 +21,7 @@ public class AddHandlerMessageHandlerTest {
     @Test
     public void shouldHandleMessageWithAddHandlerPattern() throws ReflectiveOperationException, UnknownMessageFormatException {
         var handlerName = "AnHandler";
+        when(context.getOutputStream()).thenReturn(mock(OutputStream.class));
         AddHandlerMessageHandler handler = new AddHandlerMessageHandler(context);
         handler.handleMessage("CONTROL.ADD_HANDLER " + handlerName);
         verify(context.getBroker()).addHandler(handlerName);