From 9c665b382082c21991df3c8da25d2bf7567ff3d3 Mon Sep 17 00:00:00 2001
From: Axel Uhl <axel.uhl@sap.com>
Date: Fri, 24 Jul 2020 01:29:28 +0200
Subject: [PATCH] bug5285 aftermath: made remote reference dialog robust
 against legacy case

---
 ...oteSailingServerEventsSelectionDialog.java | 34 +++++++++----------
 .../RemoteSailingServerReferenceDTO.java      |  4 ++-
 2 files changed, 20 insertions(+), 18 deletions(-)

diff --git a/java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/adminconsole/RemoteSailingServerEventsSelectionDialog.java b/java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/adminconsole/RemoteSailingServerEventsSelectionDialog.java
index 1f36e9cd005..10f1a83dabd 100644
--- a/java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/adminconsole/RemoteSailingServerEventsSelectionDialog.java
+++ b/java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/adminconsole/RemoteSailingServerEventsSelectionDialog.java
@@ -1,5 +1,13 @@
 package com.sap.sailing.gwt.ui.adminconsole;
 
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+import java.util.UUID;
+import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
+
 import com.google.gwt.event.dom.client.ClickEvent;
 import com.google.gwt.event.dom.client.ClickHandler;
 import com.google.gwt.user.client.ui.Button;
@@ -15,13 +23,6 @@ import com.sap.sailing.gwt.ui.shared.EventBaseDTO;
 import com.sap.sailing.gwt.ui.shared.RemoteSailingServerReferenceDTO;
 import com.sap.sse.gwt.client.dialog.DataEntryDialog;
 
-import java.util.ArrayList;
-import java.util.Comparator;
-import java.util.List;
-import java.util.UUID;
-import java.util.stream.Collectors;
-import java.util.stream.StreamSupport;
-
 /**
  * A dialog to set up events inclusion for given remote sailing server instance. There is a checkBox per event. If
  * <code>includeRadio</code> is selected then just selected events will be loaded. If <code>excludeRadio</code> is
@@ -51,7 +52,8 @@ public class RemoteSailingServerEventsSelectionDialog extends DataEntryDialog<Re
                 callback);
         this.stringMessages = stringMessages;
         this.referenceDTO = referenceDTO;
-        this.allEvents = StreamSupport.stream(completeRemoteServerReference.getEvents().spliterator(), false)
+        this.allEvents = completeRemoteServerReference.getEvents() == null ? Collections.emptyList() :
+            StreamSupport.stream(completeRemoteServerReference.getEvents().spliterator(), false)
                 .sorted(Comparator.comparing(EventBaseDTO::getName)).collect(Collectors.toList());
         this.selectedEvents = referenceDTO.getSelectedEvents();
     }
@@ -75,16 +77,14 @@ public class RemoteSailingServerEventsSelectionDialog extends DataEntryDialog<Re
         final Widget result;
         if (allEvents.isEmpty()) {
             getStatusLabel().setText(stringMessages.eventsListIsEmpty());
-            result = null;
-        } else {
-            eventsSelectionGrid = new Grid(allEvents.size(), 2);
-            final VerticalPanel mainPanel = new VerticalPanel();
-            mainPanel.setSpacing(10);
-            createEventsInclusionTypePanel(mainPanel);
-            addMultiSelectionPanel(mainPanel);
-            setupEventsSelectionForm(mainPanel);
-            result = mainPanel;
         }
+        eventsSelectionGrid = new Grid(allEvents.size(), 2);
+        final VerticalPanel mainPanel = new VerticalPanel();
+        mainPanel.setSpacing(10);
+        createEventsInclusionTypePanel(mainPanel);
+        addMultiSelectionPanel(mainPanel);
+        setupEventsSelectionForm(mainPanel);
+        result = mainPanel;
         return result;
     }
 
diff --git a/java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/shared/RemoteSailingServerReferenceDTO.java b/java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/shared/RemoteSailingServerReferenceDTO.java
index de1fe6b5b0d..8c499e66163 100644
--- a/java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/shared/RemoteSailingServerReferenceDTO.java
+++ b/java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/shared/RemoteSailingServerReferenceDTO.java
@@ -33,11 +33,13 @@ public class RemoteSailingServerReferenceDTO extends NamedDTO {
     public RemoteSailingServerReferenceDTO(String name, String url, boolean include,
             List<UUID> selectedEventIds, Iterable<EventBaseDTO> events) {
         this(name, url, include, selectedEventIds, events, /* error message */ null);
+        assert events != null;
     }
 
     public RemoteSailingServerReferenceDTO(String name, String url, boolean include,
             List<UUID> selectedEventIds, Iterable<EventBaseDTO> events, String lastErrorMessage) {
         super(name);
+        assert selectedEventIds != null;
         this.url = url;
         this.events = events;
         this.include = include;
@@ -46,7 +48,7 @@ public class RemoteSailingServerReferenceDTO extends NamedDTO {
     }
 
     public RemoteSailingServerReferenceDTO(String name, String url, boolean include, String lastErrorMessage) {
-        this(name, url, include, /* selectedEventIds */ null, /* events */ null, lastErrorMessage);
+        this(name, url, include, /* selectedEventIds */ Collections.emptyList(), /* events */ Collections.emptySet(), lastErrorMessage);
     }
 
     public String getUrl() {