Unify on Set.of

3 files changed, 9 insertions, 12 deletions

diff --git a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/EventDiffCalculator.java b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/EventDiffCalculator.java
index 5c29228b858..d57f32ee3cb 100644
--- a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/EventDiffCalculator.java
+++ b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/EventDiffCalculator.java
@@ -9,7 +9,6 @@ import com.yahoo.vdslib.state.NodeType;
 import com.yahoo.vdslib.state.State;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Optional;
@@ -174,8 +173,8 @@ public class EventDiffCalculator {
 
     private static void emitNodeResourceExhaustionEvents(PerStateParams params, List<Event> events, ContentCluster cluster) {
         // Feed block events are not ordered by node
-        Set<NodeResourceExhaustion> fromBlockSet = params.feedBlockFrom != null ? params.feedBlockFrom.getConcreteExhaustions() : Collections.emptySet();
-        Set<NodeResourceExhaustion> toBlockSet   = params.feedBlockTo   != null ? params.feedBlockTo.getConcreteExhaustions()   : Collections.emptySet();
+        Set<NodeResourceExhaustion> fromBlockSet = params.feedBlockFrom != null ? params.feedBlockFrom.getConcreteExhaustions() : Set.of();
+        Set<NodeResourceExhaustion> toBlockSet   = params.feedBlockTo   != null ? params.feedBlockTo.getConcreteExhaustions()   : Set.of();
 
         for (var ex : setSubtraction(fromBlockSet, toBlockSet)) {
             var info = cluster.getNodeInfo(ex.node);
diff --git a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/ResourceExhaustionCalculator.java b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/ResourceExhaustionCalculator.java
index 200a5564c64..4ed1ab967fd 100644
--- a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/ResourceExhaustionCalculator.java
+++ b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/ResourceExhaustionCalculator.java
@@ -4,7 +4,6 @@ package com.yahoo.vespa.clustercontroller.core;
 import com.yahoo.vespa.clustercontroller.core.hostinfo.HostInfo;
 
 import java.util.Collection;
-import java.util.Collections;
 import java.util.LinkedHashSet;
 import java.util.Map;
 import java.util.Objects;
@@ -60,7 +59,7 @@ public class ResourceExhaustionCalculator {
         this.feedBlockEnabled = feedBlockEnabled;
         this.feedBlockLimits = feedBlockLimits;
         this.feedBlockNoiseLevel = 0.0;
-        this.previouslyBlockedNodeResources = Collections.emptySet();
+        this.previouslyBlockedNodeResources = Set.of();
     }
 
     public ResourceExhaustionCalculator(boolean feedBlockEnabled, Map<String, Double> feedBlockLimits,
@@ -74,7 +73,7 @@ public class ResourceExhaustionCalculator {
                     .map(ex -> NodeAndResourceType.of(ex.node.getIndex(), ex.resourceType))
                     .collect(Collectors.toSet());
         } else {
-            this.previouslyBlockedNodeResources = Collections.emptySet();
+            this.previouslyBlockedNodeResources = Set.of();
         }
     }
 
@@ -124,12 +123,12 @@ public class ResourceExhaustionCalculator {
                                                               effectiveLimit, nodeInfo.getRpcAddress()));
             }
         }
-        return (exceedingLimit != null) ? exceedingLimit : Collections.emptySet();
+        return (exceedingLimit != null) ? exceedingLimit : Set.of();
     }
 
     public Set<NodeResourceExhaustion> enumerateNodeResourceExhaustions(NodeInfo nodeInfo) {
         if (!nodeInfo.isStorage()) {
-            return Collections.emptySet();
+            return Set.of();
         }
         return resourceExhaustionsFromHostInfo(nodeInfo, nodeInfo.getHostInfo());
     }
diff --git a/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/testutils/Waiter.java b/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/testutils/Waiter.java
index 9e7665e65ee..bf8ba7756e2 100644
--- a/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/testutils/Waiter.java
+++ b/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/testutils/Waiter.java
@@ -8,7 +8,6 @@ import com.yahoo.vespa.clustercontroller.core.DummyVdsNode;
 import com.yahoo.vespa.clustercontroller.core.FleetController;
 import java.time.Duration;
 import java.time.Instant;
-import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Objects;
@@ -62,13 +61,13 @@ public interface Waiter {
             return waitForState(state, data.getTimeout());
         }
         public ClusterState waitForStateInAllSpaces(String state) {
-            return waitForState(state, data.getTimeout(), true, Collections.emptySet());
+            return waitForState(state, data.getTimeout(), true, Set.of());
         }
         public ClusterState waitForStateInSpace(String space, String state) {
-            return waitForState(state, data.getTimeout(), false, Collections.singleton(space));
+            return waitForState(state, data.getTimeout(), false, Set.of(space));
         }
         public ClusterState waitForState(String state, Duration timeoutMS) {
-            return waitForState(state, timeoutMS, false, Collections.emptySet());
+            return waitForState(state, timeoutMS, false, Set.of());
         }
         public ClusterState waitForStableSystem() {
             return waitForStableSystem(data.getDummyNodes().size() / 2);