SOLR-16427: Enable error-prone PatternMatchingInstanceof rule

build-tools/missing-doclet/src/main/java/org/apache/lucene/missingdoclet/MissingDoclet.java

@@ -341,8 +341,7 @@ private boolean hasInheritedJavadocs(Element element) {
     }
 
     // Check for methods up the types tree.
-    if (element instanceof ExecutableElement) {
-      ExecutableElement thisMethod = (ExecutableElement) element;
+    if (element instanceof ExecutableElement thisMethod) {
       Iterable<Element> superTypes =
           () -> superTypeForInheritDoc(thisMethod.getEnclosingElement()).iterator();
 

gradle/validation/error-prone.gradle

@@ -457,7 +457,7 @@ allprojects { prj ->
             '-Xep:Overrides:WARN',
             // '-Xep:OverridesGuiceInjectableMethod:OFF', // we don't use guice
             '-Xep:ParameterName:WARN',
-            // '-Xep:PatternMatchingInstanceof:WARN', // todo check if useful or comment why not
+            '-Xep:PatternMatchingInstanceof:WARN',
             '-Xep:PreconditionsCheckNotNullRepeated:WARN',
             '-Xep:PrimitiveAtomicReference:WARN',
             '-Xep:ProtectedMembersInFinalClass:WARN',

solr/benchmark/src/java/org/apache/solr/bench/generators/RandomDataHistogram.java

@@ -436,8 +436,7 @@ public String toString() {
       @Override
       public boolean equals(Object o) {
         if (this == o) return true;
-        if (!(o instanceof Surrogate)) return false;
-        Surrogate surrogate = (Surrogate) o;
+        if (!(o instanceof Surrogate surrogate)) return false;
         return hashCode.equals(surrogate.hashCode)
             && identityHashcode.equals(surrogate.identityHashcode);
       }

solr/core/src/java/org/apache/solr/api/AnnotatedApi.java

@@ -261,8 +261,7 @@ static class Cmd {
     }
 
     private void readPayloadType(Type t) {
-      if (t instanceof ParameterizedType) {
-        ParameterizedType typ = (ParameterizedType) t;
+      if (t instanceof ParameterizedType typ) {
         if (typ.getRawType() == PayloadObj.class) {
           isWrappedInPayloadObj = true;
           if (typ.getActualTypeArguments().length == 0) {
@@ -271,8 +270,7 @@ private void readPayloadType(Type t) {
             return;
           }
           Type t1 = typ.getActualTypeArguments()[0];
-          if (t1 instanceof ParameterizedType) {
-            ParameterizedType parameterizedType = (ParameterizedType) t1;
+          if (t1 instanceof ParameterizedType parameterizedType) {
             parameterClass = (Class<?>) parameterizedType.getRawType();
           } else {
             parameterClass = (Class<?>) typ.getActualTypeArguments()[0];
@@ -345,9 +343,8 @@ public int hashCode() {
     public boolean equals(Object rhs) {
       if (null == rhs) return false;
       if (this == rhs) return true;
-      if (!(rhs instanceof Cmd)) return false;
+      if (!(rhs instanceof Cmd rhsCast)) return false;
 
-      final Cmd rhsCast = (Cmd) rhs;
       return Objects.equals(command, rhsCast.command)
           && Objects.equals(method, rhsCast.method)
           && Objects.equals(obj, rhsCast.obj)
@@ -373,8 +370,7 @@ public static Map<String, Object> createSchema(Method m) {
       t = types[2]; // (SolrQueryRequest req, SolrQueryResponse rsp, PayloadObj<PluginMeta>)
     if (types.length == 1) t = types[0]; // (PayloadObj<PluginMeta>)
     if (t != null) {
-      if (t instanceof ParameterizedType) {
-        ParameterizedType typ = (ParameterizedType) t;
+      if (t instanceof ParameterizedType typ) {
         if (typ.getRawType() == PayloadObj.class) {
           t = typ.getActualTypeArguments()[0];
         }

solr/core/src/java/org/apache/solr/api/ApiBag.java

@@ -122,16 +122,14 @@ protected void attachValueToNode(PathTrie<Api>.Node node, Api o) {
 
       // If 'o' and 'node.obj' aren't both AnnotatedApi's then we can't aggregate the commands, so
       // fallback to the default behavior
-      if ((!(o instanceof AnnotatedApi)) || (!(node.getObject() instanceof AnnotatedApi))) {
+      if ((!(o instanceof AnnotatedApi beingRegistered))
+          || (!(node.getObject() instanceof AnnotatedApi alreadyRegistered))) {
         super.attachValueToNode(node, o);
         return;
       }
 
-      final AnnotatedApi beingRegistered = (AnnotatedApi) o;
-      final AnnotatedApi alreadyRegistered = (AnnotatedApi) node.getObject();
-      if (alreadyRegistered instanceof CommandAggregatingAnnotatedApi) {
-        final CommandAggregatingAnnotatedApi alreadyRegisteredAsCollapsing =
-            (CommandAggregatingAnnotatedApi) alreadyRegistered;
+      if (alreadyRegistered
+          instanceof CommandAggregatingAnnotatedApi alreadyRegisteredAsCollapsing) {
         alreadyRegisteredAsCollapsing.combineWith(beingRegistered);
       } else {
         final CommandAggregatingAnnotatedApi wrapperApi =
@@ -404,11 +402,10 @@ public void registerLazy(PluginBag.PluginHolder<SolrRequestHandler> holder, Plug
 
   public static SpecProvider constructSpec(PluginInfo info) {
     Object specObj = info == null ? null : info.attributes.get("spec");
-    if (specObj != null && specObj instanceof Map) {
+    if (specObj != null && specObj instanceof Map<?, ?> map) {
       // Value from Map<String,String> can be a Map because in PluginInfo(String, Map) we assign a
       // Map<String, Object>
       // assert false : "got a map when this should only be Strings";
-      Map<?, ?> map = (Map<?, ?>) specObj;
       return () -> ValidatingJsonMap.getDeepCopy(map, 4, false);
     } else {
       return HANDLER_NAME_SPEC_PROVIDER;

solr/core/src/java/org/apache/solr/api/ContainerPluginsRegistry.java

@@ -158,8 +158,7 @@ static class PluginMetaHolder {
 
     @Override
     public boolean equals(Object obj) {
-      if (obj instanceof PluginMetaHolder) {
-        PluginMetaHolder that = (PluginMetaHolder) obj;
+      if (obj instanceof PluginMetaHolder that) {
         return Objects.equals(this.original, that.original);
       }
       return false;
@@ -466,8 +465,7 @@ public static <T extends MapWriter> Class<T> getConfigClass(ConfigurablePlugin<T
     do {
       Type[] interfaces = klas.getGenericInterfaces();
       for (Type type : interfaces) {
-        if (type instanceof ParameterizedType) {
-          ParameterizedType parameterizedType = (ParameterizedType) type;
+        if (type instanceof ParameterizedType parameterizedType) {
           Type rawType = parameterizedType.getRawType();
           if (rawType == ConfigurablePlugin.class
               ||

solr/core/src/java/org/apache/solr/cli/ExportTool.java

@@ -363,8 +363,7 @@ public synchronized void accept(SolrDocument doc) throws IOException {
               }
             }
             field = constructDateStr(field);
-            if (field instanceof List) {
-              List<?> list = (List<?>) field;
+            if (field instanceof List<?> list) {
               if (hasdate(list)) {
                 ArrayList<Object> listCopy = new ArrayList<>(list.size());
                 for (Object o : list) listCopy.add(constructDateStr(o));
@@ -443,8 +442,7 @@ public synchronized void accept(SolrDocument doc) throws IOException {
               }
             }
             field = constructDateStr(field);
-            if (field instanceof List) {
-              List<?> list = (List<?>) field;
+            if (field instanceof List<?> list) {
               if (hasdate(list)) {
                 ArrayList<Object> listCopy = new ArrayList<>(list.size());
                 for (Object o : list) listCopy.add(constructDateStr(o));

solr/core/src/java/org/apache/solr/cli/HealthcheckTool.java

@@ -286,8 +286,7 @@ public int hashCode() {
   public boolean equals(Object obj) {
     if (this == obj) return true;
     if (obj == null) return false;
-    if (!(obj instanceof ReplicaHealth)) return true;
-    ReplicaHealth that = (ReplicaHealth) obj;
+    if (!(obj instanceof ReplicaHealth that)) return true;
     return this.shard.equals(that.shard) && this.isLeader == that.isLeader;
   }
 

solr/core/src/java/org/apache/solr/cli/StreamTool.java

@@ -217,8 +217,7 @@ public void runImpl(CommandLine cli) throws Exception {
 
               Object o = tuple.get(outputHeaders[i]);
               if (o != null) {
-                if (o instanceof List) {
-                  List outfields = (List) o;
+                if (o instanceof List outfields) {
                   outLine.append(listToString(outfields, arrayDelimiter));
                 } else {
                   outLine.append(o);

solr/core/src/java/org/apache/solr/client/solrj/embedded/EmbeddedSolrServer.java

@@ -321,8 +321,7 @@ public void writeResults(ResultContext ctx, JavaBinCodec codec) throws IOExcepti
   /** A list of streams, non-null. */
   private List<ContentStream> getContentStreams(SolrRequest<?> request) throws IOException {
     if (request.getMethod() == SolrRequest.METHOD.GET) return List.of();
-    if (request instanceof ContentStreamUpdateRequest) {
-      final ContentStreamUpdateRequest csur = (ContentStreamUpdateRequest) request;
+    if (request instanceof ContentStreamUpdateRequest csur) {
       final Collection<ContentStream> cs = csur.getContentStreams();
       if (cs != null) return new ArrayList<>(cs);
     }

solr/core/src/java/org/apache/solr/cloud/Overseer.java

@@ -423,8 +423,7 @@ public void run() {
     // Return true whenever the exception thrown by ZkStateWriter is correspond
     // to a invalid state or 'bad' message (in this case, we should remove that message from queue)
     private boolean isBadMessage(Exception e) {
-      if (e instanceof KeeperException) {
-        KeeperException ke = (KeeperException) e;
+      if (e instanceof KeeperException ke) {
         return ke.code() == KeeperException.Code.NONODE
             || ke.code() == KeeperException.Code.NODEEXISTS;
       }

solr/core/src/java/org/apache/solr/cloud/OverseerTaskQueue.java

@@ -318,8 +318,7 @@ public int hashCode() {
     @Override
     public boolean equals(Object obj) {
       if (this == obj) return true;
-      if (!(obj instanceof QueueEvent)) return false;
-      QueueEvent other = (QueueEvent) obj;
+      if (!(obj instanceof QueueEvent other)) return false;
       return Objects.equals(id, other.id);
     }
 

solr/core/src/java/org/apache/solr/cloud/RecoveringCoreTermWatcher.java

@@ -76,9 +76,8 @@ public boolean onTermChanged(ShardTerms terms) {
   @Override
   public boolean equals(Object o) {
     if (this == o) return true;
-    if (!(o instanceof RecoveringCoreTermWatcher)) return false;
+    if (!(o instanceof RecoveringCoreTermWatcher that)) return false;
 
-    RecoveringCoreTermWatcher that = (RecoveringCoreTermWatcher) o;
     return coreDescriptor.getName().equals(that.coreDescriptor.getName());
   }
 

solr/core/src/java/org/apache/solr/cloud/ZkController.java

@@ -180,8 +180,7 @@ public int hashCode() {
     @Override
     public boolean equals(Object obj) {
       if (this == obj) return true;
-      if (!(obj instanceof ContextKey)) return false;
-      ContextKey other = (ContextKey) obj;
+      if (!(obj instanceof ContextKey other)) return false;
       return Objects.equals(collection, other.collection)
           && Objects.equals(coreNodeName, other.coreNodeName);
     }
@@ -2833,8 +2832,7 @@ public synchronized boolean onStateChanged(DocCollection collectionState) {
     @Override
     public boolean equals(Object o) {
       if (this == o) return true;
-      if (!(o instanceof UnloadCoreOnDeletedWatcher)) return false;
-      UnloadCoreOnDeletedWatcher that = (UnloadCoreOnDeletedWatcher) o;
+      if (!(o instanceof UnloadCoreOnDeletedWatcher that)) return false;
       return Objects.equals(coreNodeName, that.coreNodeName)
           && Objects.equals(shard, that.shard)
           && Objects.equals(coreName, that.coreName);

solr/core/src/java/org/apache/solr/cloud/api/collections/MigrateCmd.java

@@ -101,11 +101,11 @@ public void call(ClusterState clusterState, ZkNodeProps message, NamedList<Objec
           SolrException.ErrorCode.BAD_REQUEST,
           "Unknown target collection: " + sourceCollectionName);
     }
-    if (!(sourceCollection.getRouter() instanceof CompositeIdRouter)) {
+    if (!(sourceCollection.getRouter() instanceof CompositeIdRouter sourceRouter)) {
       throw new SolrException(
           SolrException.ErrorCode.BAD_REQUEST, "Source collection must use a compositeId router");
     }
-    if (!(targetCollection.getRouter() instanceof CompositeIdRouter)) {
+    if (!(targetCollection.getRouter() instanceof CompositeIdRouter targetRouter)) {
       throw new SolrException(
           SolrException.ErrorCode.BAD_REQUEST, "Target collection must use a compositeId router");
     }
@@ -115,8 +115,6 @@ public void call(ClusterState clusterState, ZkNodeProps message, NamedList<Objec
           SolrException.ErrorCode.BAD_REQUEST, "The split.key cannot be null or empty");
     }
 
-    CompositeIdRouter sourceRouter = (CompositeIdRouter) sourceCollection.getRouter();
-    CompositeIdRouter targetRouter = (CompositeIdRouter) targetCollection.getRouter();
     Collection<Slice> sourceSlices =
         sourceRouter.getSearchSlicesSingle(splitKey, null, sourceCollection);
     if (sourceSlices.isEmpty()) {

solr/core/src/java/org/apache/solr/cloud/api/collections/RoutedAlias.java

@@ -490,8 +490,7 @@ public Action(RoutedAlias sourceAlias, ActionType actionType, String targetColle
     @Override
     public boolean equals(Object o) {
       if (this == o) return true;
-      if (!(o instanceof Action)) return false;
-      Action action = (Action) o;
+      if (!(o instanceof Action action)) return false;
       return Objects.equals(sourceAlias, action.sourceAlias)
           && actionType == action.actionType
           && Objects.equals(targetCollection, action.targetCollection);

solr/core/src/java/org/apache/solr/cloud/api/collections/SplitShardCmd.java

@@ -1126,8 +1126,7 @@ public static String fillRanges(
         }
       }
     } else if (splitKey != null) {
-      if (router instanceof CompositeIdRouter) {
-        CompositeIdRouter compositeIdRouter = (CompositeIdRouter) router;
+      if (router instanceof CompositeIdRouter compositeIdRouter) {
         List<DocRouter.Range> tmpSubRanges = compositeIdRouter.partitionRangeByKey(splitKey, range);
         if (tmpSubRanges.size() == 1) {
           throw new SolrException(

solr/core/src/java/org/apache/solr/cloud/overseer/SliceMutator.java

@@ -62,8 +62,7 @@ public SliceMutator(SolrCloudManager cloudManager) {
   }
 
   static SolrZkClient getZkClient(SolrCloudManager cloudManager) {
-    if (cloudManager instanceof SolrClientCloudManager) {
-      SolrClientCloudManager manager = (SolrClientCloudManager) cloudManager;
+    if (cloudManager instanceof SolrClientCloudManager manager) {
       return manager.getZkClient();
     } else {
       return null;

solr/core/src/java/org/apache/solr/cluster/events/impl/ClusterEventProducerFactory.java

@@ -133,8 +133,7 @@ public void added(ContainerPluginsRegistry.ApiInfo plugin) {
               return;
             }
             Object instance = plugin.getInstance();
-            if (instance instanceof ClusterEventListener) {
-              ClusterEventListener listener = (ClusterEventListener) instance;
+            if (instance instanceof ClusterEventListener listener) {
               clusterEventProducer.registerListener(listener);
             } else if (instance instanceof ClusterEventProducer) {
               if (ClusterEventProducer.PLUGIN_NAME.equals(plugin.getInfo().name)) {
@@ -162,8 +161,7 @@ public void deleted(ContainerPluginsRegistry.ApiInfo plugin) {
               return;
             }
             Object instance = plugin.getInstance();
-            if (instance instanceof ClusterEventListener) {
-              ClusterEventListener listener = (ClusterEventListener) instance;
+            if (instance instanceof ClusterEventListener listener) {
               clusterEventProducer.unregisterListener(listener);
             } else if (instance instanceof ClusterEventProducer) {
               if (ClusterEventProducer.PLUGIN_NAME.equals(plugin.getInfo().name)) {

solr/core/src/java/org/apache/solr/cluster/placement/impl/MetricImpl.java

@@ -115,10 +115,9 @@ public boolean equals(Object o) {
     if (this == o) {
       return true;
     }
-    if (!(o instanceof MetricImpl)) {
+    if (!(o instanceof MetricImpl<?> that)) {
       return false;
     }
-    MetricImpl<?> that = (MetricImpl<?>) o;
     return name.equals(that.getName())
         && internalName.equals(that.getInternalName())
         && converter.equals(that.converter);

solr/core/src/java/org/apache/solr/cluster/placement/impl/NodeMetricImpl.java

@@ -88,13 +88,12 @@ public boolean equals(Object o) {
     if (this == o) {
       return true;
     }
-    if (!(o instanceof NodeMetricImpl)) {
+    if (!(o instanceof NodeMetricImpl<?> that)) {
       return false;
     }
     if (!super.equals(o)) {
       return false;
     }
-    NodeMetricImpl<?> that = (NodeMetricImpl<?>) o;
     return registry == that.registry;
   }
 

solr/core/src/java/org/apache/solr/cluster/placement/impl/SimpleClusterAbstractionsImpl.java

@@ -139,10 +139,9 @@ public boolean equals(Object obj) {
       if (obj == this) {
         return true;
       }
-      if (!(obj instanceof NodeImpl)) {
+      if (!(obj instanceof NodeImpl other)) {
         return false;
       }
-      NodeImpl other = (NodeImpl) obj;
       return Objects.equals(this.nodeName, other.nodeName);
     }
 
@@ -307,10 +306,9 @@ public boolean equals(Object obj) {
       if (obj == this) {
         return true;
       }
-      if (!(obj instanceof ShardImpl)) {
+      if (!(obj instanceof ShardImpl other)) {
         return false;
       }
-      ShardImpl other = (ShardImpl) obj;
       return Objects.equals(this.shardName, other.shardName)
           && Objects.equals(this.collection, other.collection)
           && Objects.equals(this.shardState, other.shardState)
@@ -467,10 +465,9 @@ public boolean equals(Object obj) {
       if (obj == this) {
         return true;
       }
-      if (!(obj instanceof ReplicaImpl)) {
+      if (!(obj instanceof ReplicaImpl other)) {
         return false;
       }
-      ReplicaImpl other = (ReplicaImpl) obj;
       return Objects.equals(this.replicaName, other.replicaName)
           && Objects.equals(this.coreName, other.coreName)
           && Objects.equals(this.shard, other.shard)

solr/core/src/java/org/apache/solr/cluster/placement/plugins/OrderedNodePlacementPlugin.java

@@ -555,10 +555,9 @@ public int hashCode() {
 
     @Override
     public boolean equals(Object o) {
-      if (!(o instanceof WeightedNode)) {
+      if (!(o instanceof WeightedNode on)) {
         return false;
       } else {
-        WeightedNode on = (WeightedNode) o;
         if (this.node == null) {
           return on.node == null;
         } else {

solr/core/src/java/org/apache/solr/core/ClusterSingletons.java

@@ -69,8 +69,7 @@ public void added(ContainerPluginsRegistry.ApiInfo plugin) {
             }
             // register new api
             Object instance = plugin.getInstance();
-            if (instance instanceof ClusterSingleton) {
-              ClusterSingleton singleton = (ClusterSingleton) instance;
+            if (instance instanceof ClusterSingleton singleton) {
               singletonMap.put(singleton.getName(), singleton);
               // check to see if we should immediately start this singleton
               if (isReady() && runSingletons.get()) {
@@ -89,8 +88,7 @@ public void deleted(ContainerPluginsRegistry.ApiInfo plugin) {
               return;
             }
             Object instance = plugin.getInstance();
-            if (instance instanceof ClusterSingleton) {
-              ClusterSingleton singleton = (ClusterSingleton) instance;
+            if (instance instanceof ClusterSingleton singleton) {
               singleton.stop();
               singletonMap.remove(singleton.getName());
             }