review:

add equals and hashCode to ModifySplitBrainResolver and ModifySplitBrainResolverResponse;
add package-info.java;

Signed-off-by: Stefan Maute <stefan.maute@bosch.io>

base/service/src/main/java/org/eclipse/ditto/base/service/cluster/DittoSplitBrainResolver.java

@@ -42,6 +42,7 @@ final class DittoSplitBrainResolver extends AbstractActor {
     @Nullable
     private ActorRef splitBrainResolverActor;
 
+    @SuppressWarnings("unused")
     private DittoSplitBrainResolver(final Props splitBrainResolverProps) {
         this.splitBrainResolverProps = splitBrainResolverProps;
         final Duration autoEnableAfter = getAutoEnableAfter();
@@ -52,6 +53,10 @@ private DittoSplitBrainResolver(final Props splitBrainResolverProps) {
         LOGGER.info("SBR will be automatically enabled after <{}>", autoEnableAfter);
     }
 
+    static Props props(@Nullable final Props splitBrainResolverProps) {
+        return Props.create(DittoSplitBrainResolver.class, splitBrainResolverProps);
+    }
+
     private Duration getAutoEnableAfter() {
         try {
             return context().system().settings().config().getDuration(SBR_ENABLING_DELAY);
@@ -69,9 +74,6 @@ public Receive createReceive() {
                 .build();
     }
 
-    static Props props(@Nullable final Props splitBrainResolverProps) {
-        return Props.create(DittoSplitBrainResolver.class, splitBrainResolverProps);
-    }
 
     private ActorRef startChildActor(final Props props) {
         return getContext().actorOf(props);
@@ -82,10 +84,10 @@ private void updateEnabled(final ModifySplitBrainResolver modifySplitBrainResolv
             autoEnabling.cancel();
         }
         if (modifySplitBrainResolver.isEnabled() && splitBrainResolverActor == null) {
-            LOGGER.info("Enabling akka split brain resolver");
+            LOGGER.info("Enabling Akka split rain resolver");
             splitBrainResolverActor = startChildActor(splitBrainResolverProps);
         } else if (!modifySplitBrainResolver.isEnabled() && splitBrainResolverActor != null) {
-            LOGGER.info("Stopping akka split brain resolver");
+            LOGGER.info("Stopping Akka split brain resolver");
             getContext().stop(splitBrainResolverActor);
             splitBrainResolverActor = null;
         }

base/service/src/main/java/org/eclipse/ditto/base/service/cluster/DittoSplitBrainResolverProvider.java

@@ -54,7 +54,7 @@ public Option<Props> downingActorProps() {
             final Props splitBrainResolverProps = splitBrainResolverProvider.downingActorProps().get();
             return Option.apply(DittoSplitBrainResolver.props(splitBrainResolverProps));
         } catch (final Exception e) {
-            final String msg = "Could not create ditto split brain resolver props.";
+            final String msg = "Could not create Ditto split brain resolver props.";
             LOGGER.error(msg, e);
             throw new DittoConfigError(msg, e);
         }

base/service/src/main/java/org/eclipse/ditto/base/service/cluster/ModifySplitBrainResolver.java

@@ -12,8 +12,11 @@
  */
 package org.eclipse.ditto.base.service.cluster;
 
+import java.util.Objects;
 import java.util.function.Predicate;
 
+import javax.annotation.Nullable;
+
 import org.eclipse.ditto.base.model.headers.DittoHeaders;
 import org.eclipse.ditto.base.model.json.FieldType;
 import org.eclipse.ditto.base.model.json.JsonParsableCommand;
@@ -29,7 +32,7 @@
 @JsonParsableCommand(typePrefix = ModifySplitBrainResolver.PREFIX, name = ModifySplitBrainResolver.NAME)
 public final class ModifySplitBrainResolver extends AbstractCommand<ModifySplitBrainResolver> {
 
-    private static final JsonFieldDefinition<Boolean> ENABLED =
+    public static final JsonFieldDefinition<Boolean> ENABLED_FIELD_KEY =
             JsonFieldDefinition.ofBoolean("enabled", FieldType.REGULAR, JsonSchemaVersion.V_2);
 
     static final String PREFIX = "ditto.sbr:";
@@ -49,7 +52,7 @@ public boolean isEnabled() {
 
     public static ModifySplitBrainResolver fromJson(final JsonObject jsonObject, final DittoHeaders dittoHeaders) {
         return new CommandJsonDeserializer<ModifySplitBrainResolver>(TYPE, jsonObject).deserialize(() -> {
-            final boolean enabled = jsonObject.getValue(ENABLED).orElseThrow();
+            final boolean enabled = jsonObject.getValue(ENABLED_FIELD_KEY).orElseThrow();
 
             return new ModifySplitBrainResolver(dittoHeaders, enabled);
         });
@@ -62,7 +65,7 @@ static ModifySplitBrainResolver of(final boolean enabled) {
     @Override
     protected void appendPayload(final JsonObjectBuilder jsonObjectBuilder, final JsonSchemaVersion schemaVersion,
             final Predicate<JsonField> predicate) {
-        jsonObjectBuilder.set(ENABLED, enabled, schemaVersion.and(predicate));
+        jsonObjectBuilder.set(ENABLED_FIELD_KEY, enabled, schemaVersion.and(predicate));
     }
 
     @Override
@@ -90,4 +93,34 @@ public String getResourceType() {
         return "sbr";
     }
 
+    @Override
+    protected boolean canEqual(@Nullable final Object other) {
+        return other instanceof ModifySplitBrainResolver;
+    }
+
+    @Override
+    public boolean equals(final Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        if (!super.equals(o)) return false;
+        final ModifySplitBrainResolver that = (ModifySplitBrainResolver) o;
+        return enabled == that.enabled;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(super.hashCode(), enabled);
+    }
+
+    @Override
+    public String toString() {
+        return getClass().getSimpleName() + " [" +
+                "enabled=" + enabled +
+                "]";
+    }
+
 }

base/service/src/main/java/org/eclipse/ditto/base/service/cluster/ModifySplitBrainResolverResponse.java

@@ -12,17 +12,18 @@
  */
 package org.eclipse.ditto.base.service.cluster;
 
+import java.util.Objects;
 import java.util.function.Predicate;
 
+import javax.annotation.Nullable;
+
 import org.eclipse.ditto.base.model.common.HttpStatus;
 import org.eclipse.ditto.base.model.headers.DittoHeaders;
-import org.eclipse.ditto.base.model.json.FieldType;
 import org.eclipse.ditto.base.model.json.JsonParsableCommandResponse;
 import org.eclipse.ditto.base.model.json.JsonSchemaVersion;
 import org.eclipse.ditto.base.model.signals.commands.AbstractCommandResponse;
 import org.eclipse.ditto.base.model.signals.commands.CommandResponseJsonDeserializer;
 import org.eclipse.ditto.json.JsonField;
-import org.eclipse.ditto.json.JsonFieldDefinition;
 import org.eclipse.ditto.json.JsonObject;
 import org.eclipse.ditto.json.JsonObjectBuilder;
 import org.eclipse.ditto.json.JsonPointer;
@@ -31,9 +32,6 @@
 public final class ModifySplitBrainResolverResponse
         extends AbstractCommandResponse<ModifySplitBrainResolverResponse> {
 
-    private static final JsonFieldDefinition<Boolean> ENABLED =
-            JsonFieldDefinition.ofBoolean("enabled", FieldType.REGULAR, JsonSchemaVersion.V_2);
-
     static final String PREFIX = "ditto.sbr:";
     static final String NAME = "modifyResponse";
     public static final String TYPE = PREFIX + NAME;
@@ -42,7 +40,7 @@ public final class ModifySplitBrainResolverResponse
             CommandResponseJsonDeserializer.newInstance(TYPE,
                     context -> {
                         final JsonObject jsonObject = context.getJsonObject();
-                        final boolean enabled = jsonObject.getValue(ENABLED).orElseThrow();
+                        final boolean enabled = jsonObject.getValue(ModifySplitBrainResolver.ENABLED_FIELD_KEY).orElseThrow();
                         return new ModifySplitBrainResolverResponse(context.getDittoHeaders(), enabled);
                     });
 
@@ -70,7 +68,7 @@ public static ModifySplitBrainResolverResponse fromJson(final JsonObject jsonObj
     @Override
     protected void appendPayload(final JsonObjectBuilder jsonObjectBuilder, final JsonSchemaVersion schemaVersion,
             final Predicate<JsonField> predicate) {
-        jsonObjectBuilder.set(ENABLED, enabled, schemaVersion.and(predicate));
+        jsonObjectBuilder.set(ModifySplitBrainResolver.ENABLED_FIELD_KEY, enabled, schemaVersion.and(predicate));
     }
 
     @Override
@@ -88,4 +86,34 @@ public ModifySplitBrainResolverResponse setDittoHeaders(final DittoHeaders ditto
         return new ModifySplitBrainResolverResponse(dittoHeaders, enabled);
     }
 
+    @Override
+    protected boolean canEqual(@Nullable final Object other) {
+        return other instanceof ModifySplitBrainResolverResponse;
+    }
+
+    @Override
+    public boolean equals(final Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        if (!super.equals(o)) return false;
+        final ModifySplitBrainResolverResponse that = (ModifySplitBrainResolverResponse) o;
+        return enabled == that.enabled;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(super.hashCode(), enabled);
+    }
+
+    @Override
+    public String toString() {
+        return getClass().getSimpleName() + " [" +
+                "enabled=" + enabled +
+                "]";
+    }
+
 }

base/service/src/main/java/org/eclipse/ditto/base/service/cluster/package-info.java

@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2022 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+@org.eclipse.ditto.utils.jsr305.annotations.AllValuesAreNonnullByDefault
+package org.eclipse.ditto.base.service.cluster;