[grid] Replace Guava with Java equivalent in Distributor package

java/src/org/openqa/selenium/grid/distributor/DrainNode.java

@@ -19,8 +19,8 @@
 
 import static org.openqa.selenium.remote.http.Contents.asJson;
 
-import com.google.common.collect.ImmutableMap;
 import java.io.UncheckedIOException;
+import java.util.Map;
 import java.util.Objects;
 import org.openqa.selenium.grid.data.NodeId;
 import org.openqa.selenium.remote.http.HttpHandler;
@@ -45,12 +45,11 @@ public HttpResponse execute(HttpRequest req) throws UncheckedIOException {
     if (value) {
       response.setContent(
           asJson(
-              ImmutableMap.of(
-                  "value", value, "message", "Node status was successfully set to draining.")));
+              Map.of("value", value, "message", "Node status was successfully set to draining.")));
     } else {
       response.setContent(
           asJson(
-              ImmutableMap.of(
+              Map.of(
                   "value",
                   value,
                   "message",

java/src/org/openqa/selenium/grid/distributor/GetDistributorStatus.java

@@ -19,7 +19,7 @@
 
 import static org.openqa.selenium.remote.http.Contents.asJson;
 
-import com.google.common.collect.ImmutableMap;
+import java.util.Map;
 import org.openqa.selenium.grid.data.DistributorStatus;
 import org.openqa.selenium.internal.Require;
 import org.openqa.selenium.remote.http.HttpHandler;
@@ -38,6 +38,6 @@ class GetDistributorStatus implements HttpHandler {
   public HttpResponse execute(HttpRequest req) {
     DistributorStatus status = distributor.getStatus();
 
-    return new HttpResponse().setContent(asJson(ImmutableMap.of("value", status)));
+    return new HttpResponse().setContent(asJson(Map.of("value", status)));
   }
 }

java/src/org/openqa/selenium/grid/distributor/StatusHandler.java

@@ -19,7 +19,7 @@
 
 import static org.openqa.selenium.remote.http.Contents.asJson;
 
-import com.google.common.collect.ImmutableMap;
+import java.util.Map;
 import org.openqa.selenium.grid.data.DistributorStatus;
 import org.openqa.selenium.internal.Require;
 import org.openqa.selenium.remote.http.HttpHandler;
@@ -38,10 +38,10 @@ class StatusHandler implements HttpHandler {
   public HttpResponse execute(HttpRequest req) {
     DistributorStatus status = distributor.getStatus();
 
-    ImmutableMap<String, Object> report =
-        ImmutableMap.of(
+    Map<String, Object> report =
+        Map.of(
             "value",
-            ImmutableMap.of(
+            Map.of(
                 "ready",
                 status.hasCapacity(),
                 "message",

java/src/org/openqa/selenium/grid/distributor/httpd/DefaultDistributorConfig.java

@@ -17,20 +17,20 @@
 
 package org.openqa.selenium.grid.distributor.httpd;
 
-import com.google.common.collect.ImmutableMap;
+import java.util.Map;
 import org.openqa.selenium.grid.config.MapConfig;
 
 class DefaultDistributorConfig extends MapConfig {
 
   DefaultDistributorConfig() {
     super(
-        ImmutableMap.of(
+        Map.of(
             "events",
-            ImmutableMap.of(
+            Map.of(
                 "publish", "tcp://*:4442",
                 "subscribe", "tcp://*:4443",
                 "bind", true),
             "server",
-            ImmutableMap.of("port", 5553)));
+            Map.of("port", 5553)));
   }
 }

java/src/org/openqa/selenium/grid/distributor/httpd/DistributorServer.java

@@ -28,13 +28,12 @@
 import static org.openqa.selenium.remote.http.Route.get;
 
 import com.google.auto.service.AutoService;
-import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.ImmutableSet;
 import com.google.common.net.MediaType;
 import java.io.Closeable;
 import java.io.IOException;
 import java.io.UncheckedIOException;
 import java.util.Collections;
+import java.util.Map;
 import java.util.Set;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -69,7 +68,7 @@ public String getDescription() {
 
   @Override
   public Set<Role> getConfigurableRoles() {
-    return ImmutableSet.of(
+    return Set.of(
         DISTRIBUTOR_ROLE, EVENT_BUS_ROLE, HTTPD_ROLE, SESSION_MAP_ROLE, SESSION_QUEUE_ROLE);
   }
 
@@ -113,9 +112,9 @@ protected Handlers createHandlers(Config config) {
                             new HttpResponse()
                                 .setContent(
                                     Contents.asJson(
-                                        ImmutableMap.of(
+                                        Map.of(
                                             "value",
-                                            ImmutableMap.of(
+                                            Map.of(
                                                 "ready",
                                                 true,
                                                 "message",

java/src/org/openqa/selenium/grid/distributor/local/LocalDistributor.java

@@ -28,7 +28,6 @@
 import static org.openqa.selenium.remote.tracing.Tags.EXCEPTION;
 
 import com.google.common.annotations.VisibleForTesting;
-import com.google.common.collect.ImmutableSet;
 import java.io.Closeable;
 import java.io.UncheckedIOException;
 import java.net.URI;
@@ -245,7 +244,7 @@ public static Distributor create(Config config) {
   @Override
   public boolean isReady() {
     try {
-      return ImmutableSet.of(bus, sessions).parallelStream()
+      return Set.of(bus, sessions).parallelStream()
           .map(HasReadyState::isReady)
           .reduce(true, Boolean::logicalAnd);
     } catch (RuntimeException e) {

java/src/org/openqa/selenium/grid/distributor/local/LocalGridModel.java

@@ -21,7 +21,6 @@
 import static org.openqa.selenium.grid.data.Availability.DRAINING;
 import static org.openqa.selenium.grid.data.Availability.UP;
 
-import com.google.common.collect.ImmutableSet;
 import java.time.Instant;
 import java.util.Collections;
 import java.util.HashMap;
@@ -360,7 +359,7 @@ public Set<NodeStatus> getSnapshot() {
     Lock readLock = this.lock.readLock();
     readLock.lock();
     try {
-      return ImmutableSet.copyOf(nodes);
+      return Set.copyOf(nodes);
     } finally {
       readLock.unlock();
     }

java/src/org/openqa/selenium/grid/distributor/local/LocalNodeRegistry.java

@@ -22,8 +22,6 @@
 import static org.openqa.selenium.grid.data.Availability.UP;
 import static org.openqa.selenium.internal.Debug.getDebugLogLevel;
 
-import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.ImmutableSet;
 import java.net.URI;
 import java.time.Duration;
 import java.util.ArrayList;
@@ -306,11 +304,11 @@ public void updateNodeAvailability(URI nodeUri, NodeId id, Availability availabi
 
   @Override
   public void runHealthChecks() {
-    ImmutableMap<NodeId, Runnable> nodeHealthChecks;
+    Map<NodeId, Runnable> nodeHealthChecks;
     Lock readLock = this.lock.readLock();
     readLock.lock();
     try {
-      nodeHealthChecks = ImmutableMap.copyOf(allChecks);
+      nodeHealthChecks = Map.copyOf(allChecks);
     } finally {
       readLock.unlock();
     }
@@ -363,7 +361,7 @@ public Set<NodeStatus> getAvailableNodes() {
       return model.getSnapshot().stream()
           // Filter nodes are UP and have capacity (available slots)
           .filter(node -> UP.equals(node.getAvailability()) && node.hasCapacity())
-          .collect(ImmutableSet.toImmutableSet());
+          .collect(Collectors.toUnmodifiableSet());
     } finally {
       readLock.unlock();
     }
@@ -405,7 +403,7 @@ public long getDownNodeCount() {
   @Override
   public boolean isReady() {
     try {
-      return ImmutableSet.of(bus).parallelStream()
+      return Set.of(bus).parallelStream()
           .map(HasReadyState::isReady)
           .reduce(true, Boolean::logicalAnd);
     } catch (RuntimeException e) {

java/src/org/openqa/selenium/grid/distributor/selector/DefaultSlotSelector.java

@@ -17,13 +17,15 @@
 
 package org.openqa.selenium.grid.distributor.selector;
 
-import static com.google.common.collect.ImmutableSet.toImmutableSet;
 import static org.openqa.selenium.grid.data.Availability.UP;
 
 import com.google.common.annotations.VisibleForTesting;
+import java.util.Collections;
 import java.util.Comparator;
+import java.util.LinkedHashSet;
 import java.util.Locale;
 import java.util.Set;
+import java.util.stream.Collectors;
 import org.openqa.selenium.Capabilities;
 import org.openqa.selenium.grid.config.Config;
 import org.openqa.selenium.grid.data.NodeStatus;
@@ -69,7 +71,11 @@ public Set<SlotId> selectSlot(
                     .filter(slot -> slot.getSession() == null)
                     .filter(slot -> slot.isSupporting(capabilities, slotMatcher))
                     .map(Slot::getId))
-        .collect(toImmutableSet());
+        // Any collector used here needs to maintain the insertion order
+        .collect(
+            Collectors.collectingAndThen(
+                Collectors.toCollection(LinkedHashSet::new),
+                set -> Collections.unmodifiableSet(new LinkedHashSet<>(set))));
   }
 
   @VisibleForTesting

java/src/org/openqa/selenium/grid/distributor/selector/GreedySlotSelector.java

@@ -17,11 +17,13 @@
 
 package org.openqa.selenium.grid.distributor.selector;
 
-import static com.google.common.collect.ImmutableSet.toImmutableSet;
 import static org.openqa.selenium.grid.data.Availability.UP;
 
+import java.util.Collections;
 import java.util.Comparator;
+import java.util.LinkedHashSet;
 import java.util.Set;
+import java.util.stream.Collectors;
 import org.openqa.selenium.Capabilities;
 import org.openqa.selenium.grid.config.Config;
 import org.openqa.selenium.grid.data.NodeStatus;
@@ -69,6 +71,9 @@ public Set<SlotId> selectSlot(
                     .filter(slot -> slot.getSession() == null)
                     .filter(slot -> slot.isSupporting(capabilities, slotMatcher))
                     .map(Slot::getId))
-        .collect(toImmutableSet());
+        .collect(
+            Collectors.collectingAndThen(
+                Collectors.toCollection(LinkedHashSet::new),
+                set -> Collections.unmodifiableSet(new LinkedHashSet<>(set))));
   }
 }