Unify on Map.of

7 files changed, 22 insertions, 31 deletions

diff --git a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/AnnotatedClusterState.java b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/AnnotatedClusterState.java
index e0ddf16ab5f..7991e1c34b6 100644
--- a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/AnnotatedClusterState.java
+++ b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/AnnotatedClusterState.java
@@ -4,7 +4,6 @@ package com.yahoo.vespa.clustercontroller.core;
 import com.yahoo.vdslib.state.ClusterState;
 import com.yahoo.vdslib.state.Node;
 
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
@@ -47,7 +46,7 @@ public class AnnotatedClusterState implements Cloneable {
                                  Map<Node, NodeStateReason> nodeStateReasons) {
         this.clusterState = Objects.requireNonNull(clusterState, "Cluster state cannot be null");
         this.clusterStateReason = Objects.requireNonNull(clusterStateReason, "Cluster state reason cannot be null");
-        this.nodeStateReasons = Objects.requireNonNull(nodeStateReasons, "Node state reasons cannot be null");
+        this.nodeStateReasons = Map.copyOf(Objects.requireNonNull(nodeStateReasons, "Node state reasons cannot be null"));
     }
 
     public static AnnotatedClusterState emptyState() {
@@ -59,7 +58,7 @@ public class AnnotatedClusterState implements Cloneable {
     }
 
     static Map<Node, NodeStateReason> emptyNodeStateReasons() {
-        return Collections.emptyMap();
+        return Map.of();
     }
 
     public ClusterState getClusterState() {
@@ -67,7 +66,7 @@ public class AnnotatedClusterState implements Cloneable {
     }
 
     public Map<Node, NodeStateReason> getNodeStateReasons() {
-        return Collections.unmodifiableMap(nodeStateReasons);
+        return nodeStateReasons;
     }
 
     public Optional<ClusterStateReason> getClusterStateReason() {
diff --git a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/ClusterStateBundle.java b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/ClusterStateBundle.java
index 53a39968720..d99d46c11ce 100644
--- a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/ClusterStateBundle.java
+++ b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/ClusterStateBundle.java
@@ -4,7 +4,6 @@ package com.yahoo.vespa.clustercontroller.core;
 import com.yahoo.vdslib.state.ClusterState;
 
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
@@ -56,7 +55,7 @@ public class ClusterStateBundle {
         public FeedBlock(boolean blockFeedInCluster, String description) {
             this.blockFeedInCluster = blockFeedInCluster;
             this.description = description;
-            this.concreteExhaustions = Collections.emptySet();
+            this.concreteExhaustions = Set.of();
         }
 
         public FeedBlock(boolean blockFeedInCluster, String description,
@@ -165,14 +164,10 @@ public class ClusterStateBundle {
                 return ClusterStateBundle.ofBaselineOnly(baselineState, feedBlock, deferredActivation);
             }
             Map<String, AnnotatedClusterState> derived;
-            if (explicitDerivedStates != null) {
-                derived = explicitDerivedStates;
-            } else {
-                derived = bucketSpaces.stream()
-                        .collect(Collectors.toMap(
-                                Function.identity(),
-                                s -> stateDeriver.derivedFrom(baselineState, s)));
-            }
+            derived = Objects.requireNonNullElseGet(explicitDerivedStates, () -> bucketSpaces.stream()
+                    .collect(Collectors.toUnmodifiableMap(
+                            Function.identity(),
+                            s -> stateDeriver.derivedFrom(baselineState, s))));
             return new ClusterStateBundle(baselineState, derived, feedBlock, deferredActivation);
         }
     }
@@ -186,7 +181,7 @@ public class ClusterStateBundle {
                                FeedBlock feedBlock,
                                boolean deferredActivation) {
         this.baselineState = baselineState;
-        this.derivedBucketSpaceStates = Collections.unmodifiableMap(derivedBucketSpaceStates);
+        this.derivedBucketSpaceStates = Map.copyOf(derivedBucketSpaceStates);
         this.feedBlock = feedBlock;
         this.deferredActivation = deferredActivation;
     }
@@ -209,11 +204,11 @@ public class ClusterStateBundle {
     public static ClusterStateBundle ofBaselineOnly(AnnotatedClusterState baselineState,
                                                     FeedBlock feedBlock,
                                                     boolean deferredActivation) {
-        return new ClusterStateBundle(baselineState, Collections.emptyMap(), feedBlock, deferredActivation);
+        return new ClusterStateBundle(baselineState, Map.of(), feedBlock, deferredActivation);
     }
 
     public static ClusterStateBundle ofBaselineOnly(AnnotatedClusterState baselineState) {
-        return new ClusterStateBundle(baselineState, Collections.emptyMap());
+        return new ClusterStateBundle(baselineState, Map.of());
     }
 
     public static ClusterStateBundle empty() {
@@ -238,7 +233,7 @@ public class ClusterStateBundle {
         AnnotatedClusterState clonedBaseline = baselineState.cloneWithClusterState(
                 mapper.apply(baselineState.getClusterState().clone()));
         Map<String, AnnotatedClusterState> clonedDerived = derivedBucketSpaceStates.entrySet().stream()
-                .collect(Collectors.toMap(e -> e.getKey(), e -> e.getValue().cloneWithClusterState(
+                .collect(Collectors.toMap(Map.Entry::getKey, e -> e.getValue().cloneWithClusterState(
                         mapper.apply(e.getValue().getClusterState().clone()))));
         return new ClusterStateBundle(clonedBaseline, clonedDerived, feedBlock, deferredActivation);
     }
diff --git a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/FleetControllerOptions.java b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/FleetControllerOptions.java
index a0efaa70b58..44b2c8833db 100644
--- a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/FleetControllerOptions.java
+++ b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/FleetControllerOptions.java
@@ -10,7 +10,6 @@ import com.yahoo.vespa.clustercontroller.core.database.ZooKeeperDatabaseFactory;
 
 import java.time.Duration;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
@@ -433,7 +432,7 @@ public class FleetControllerOptions {
         private double minMergeCompletionRatio = 1.0;
         private int maxDivergentNodesPrintedInTaskErrorMessages = 10;
         private boolean clusterFeedBlockEnabled = false;
-        private Map<String, Double> clusterFeedBlockLimit = Collections.emptyMap();
+        private Map<String, Double> clusterFeedBlockLimit = Map.of();
         private double clusterFeedBlockNoiseLevel = 0.01;
         private int maxNumberOfGroupsAllowedToBeDown = 1;
         private Function<FleetControllerContext, DatabaseFactory> dbFactoryFn = ZooKeeperDatabaseFactory::new;
diff --git a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/rpc/SlimeClusterStateBundleCodec.java b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/rpc/SlimeClusterStateBundleCodec.java
index 12db5c27375..3a6b9a635fa 100644
--- a/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/rpc/SlimeClusterStateBundleCodec.java
+++ b/clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/rpc/SlimeClusterStateBundleCodec.java
@@ -41,11 +41,10 @@ public class SlimeClusterStateBundleCodec implements ClusterStateBundleCodec, En
         // TODO add another function that is not toString for this..!
         states.setString("baseline", stateBundle.getBaselineClusterState().toString());
         Cursor spaces = states.setObject("spaces");
-        stateBundle.getDerivedBucketSpaceStates().entrySet()
-                .forEach(entry -> spaces.setString(entry.getKey(), entry.getValue().toString()));
+        stateBundle.getDerivedBucketSpaceStates().forEach((key, value) -> spaces.setString(key, value.toString()));
 
         // Only bother to encode feed block state if cluster is actually blocked
-        if (stateBundle.getFeedBlock().map(fb -> fb.blockFeedInCluster()).orElse(false)) {
+        if (stateBundle.getFeedBlock().map(ClusterStateBundle.FeedBlock::blockFeedInCluster).orElse(false)) {
             Cursor feedBlock = root.setObject("feed-block");
             feedBlock.setBool("block-feed-in-cluster", true);
             feedBlock.setString("description", stateBundle.getFeedBlock().get().getDescription());
diff --git a/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ClusterStateBundleUtil.java b/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ClusterStateBundleUtil.java
index 7c39135291c..8280706bcd2 100644
--- a/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ClusterStateBundleUtil.java
+++ b/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ClusterStateBundleUtil.java
@@ -14,13 +14,13 @@ public class ClusterStateBundleUtil {
 
     public static ClusterStateBundle.Builder makeBundleBuilder(String baselineState, StateMapping... bucketSpaceStates) {
         return ClusterStateBundle.builder(AnnotatedClusterState.withoutAnnotations(ClusterState.stateFromString(baselineState)))
-                .explicitDerivedStates(Stream.of(bucketSpaceStates).collect(Collectors.toMap(sm -> sm.bucketSpace,
+                .explicitDerivedStates(Stream.of(bucketSpaceStates).collect(Collectors.toUnmodifiableMap(sm -> sm.bucketSpace,
                         sm -> AnnotatedClusterState.withoutAnnotations(sm.state))));
     }
 
     public static ClusterStateBundle makeBundle(String baselineState, StateMapping... bucketSpaceStates) {
         return ClusterStateBundle.of(AnnotatedClusterState.withoutAnnotations(ClusterState.stateFromString(baselineState)),
-                Stream.of(bucketSpaceStates).collect(Collectors.toMap(sm -> sm.bucketSpace,
+                Stream.of(bucketSpaceStates).collect(Collectors.toUnmodifiableMap(sm -> sm.bucketSpace,
                         sm -> AnnotatedClusterState.withoutAnnotations(sm.state))));
     }
 
diff --git a/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ContentClusterHtmlRendererTest.java b/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ContentClusterHtmlRendererTest.java
index 175b7de8f4f..8048e77b05c 100644
--- a/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ContentClusterHtmlRendererTest.java
+++ b/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ContentClusterHtmlRendererTest.java
@@ -11,7 +11,6 @@ import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
 import java.io.IOException;
-import java.util.Collections;
 import java.util.Map;
 import java.util.TreeMap;
 
@@ -53,7 +52,7 @@ public class ContentClusterHtmlRendererTest {
                 statsAggregator,
                 1.0,
                 10,
-                Collections.emptyMap(),
+                Map.of(),
                 eventLog,
                 "pathPrefix",
                 "name");
diff --git a/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ResourceUsageStatsTest.java b/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ResourceUsageStatsTest.java
index b4246806079..168fe6521d5 100644
--- a/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ResourceUsageStatsTest.java
+++ b/clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ResourceUsageStatsTest.java
@@ -4,7 +4,7 @@ package com.yahoo.vespa.clustercontroller.core;
 import org.junit.jupiter.api.Test;
 
 import java.util.Collection;
-import java.util.Collections;
+import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 
@@ -46,20 +46,20 @@ public class ResourceUsageStatsTest {
 
     @Test
     void nodes_above_limit_is_zero_without_feed_block_status() {
-        var stats = ResourceUsageStats.calculateFrom(Collections.emptyList(), Collections.emptyMap(), Optional.empty());
+        var stats = ResourceUsageStats.calculateFrom(List.of(), Map.of(), Optional.empty());
         assertEquals(0, stats.getNodesAboveLimit());
     }
 
     @Test
     void nodes_above_limit_is_equal_to_node_resource_exhaustions() {
-        var stats = ResourceUsageStats.calculateFrom(Collections.emptyList(), Collections.emptyMap(),
+        var stats = ResourceUsageStats.calculateFrom(List.of(), Map.of(),
                 createFeedBlock(exhaustion(1, "disk"), exhaustion(2, "memory")));
         assertEquals(2, stats.getNodesAboveLimit());
     }
 
     @Test
     void nodes_above_limit_counts_each_node_only_once() {
-        var stats = ResourceUsageStats.calculateFrom(Collections.emptyList(), Collections.emptyMap(),
+        var stats = ResourceUsageStats.calculateFrom(List.of(), Map.of(),
                 createFeedBlock(exhaustion(1, "disk"), exhaustion(1, "memory")));
         assertEquals(1, stats.getNodesAboveLimit());
     }