Replace NOT operator with explicit false check - part 8 (#68625)

Part 8.

We have an in-house rule to compare explicitly against `false` instead
of using the logical not operator (`!`). However, this hasn't
historically been enforced, meaning that there are many violations in
the source at present.

We now have a Checkstyle rule that can detect these cases, but before we
can turn it on, we need to fix the existing violations. This is being
done over a series of PRs, since there are a lot to fix.

Author: pugnascotia

client/benchmark/src/main/java/org/elasticsearch/client/benchmark/metrics/MetricsCalculator.java

@@ -53,7 +53,7 @@ private static List<Metrics> calculateMetricsPerOperation(Map<String, List<Sampl
 
             metrics.add(new Metrics(operationAndMetrics.getKey(),
                 samples.stream().filter((r) -> r.isSuccess()).count(),
-                samples.stream().filter((r) -> !r.isSuccess()).count(),
+                samples.stream().filter((r) -> r.isSuccess() == false).count(),
                 // throughput calculation is based on the total (Wall clock) time it took to generate all samples
                 calculateThroughput(samples.size(), latestEnd - firstStart),
                 // convert ns -> ms without losing precision

client/rest-high-level/src/main/java/org/elasticsearch/client/ml/job/config/DefaultDetectorDescription.java

@@ -80,6 +80,6 @@ private static String quoteField(String field) {
     }
 
     private static boolean isNotNullOrEmpty(String arg) {
-        return !Strings.isNullOrEmpty(arg);
+        return Strings.isNullOrEmpty(arg) == false;
     }
 }

libs/core/src/main/java/org/elasticsearch/common/concurrent/CompletableContext.java

@@ -27,7 +27,7 @@ public void addListener(BiConsumer<T, ? super Exception> listener) {
             if (t == null) {
                 listener.accept(v, null);
             } else {
-                assert !(t instanceof Error) : "Cannot be error";
+                assert (t instanceof Error) == false: "Cannot be error";
                 listener.accept(v, (Exception) t);
             }
         };

libs/dissect/src/main/java/org/elasticsearch/dissect/DissectParser.java

@@ -117,7 +117,7 @@ public DissectParser(String pattern, String appendSeparator) {
         }
         this.maxMatches = matchPairs.size();
         this.maxResults = Long.valueOf(matchPairs.stream()
-            .filter(dissectPair -> !dissectPair.getKey().skip()).map(KEY_NAME).distinct().count()).intValue();
+            .filter(dissectPair -> dissectPair.getKey().skip() == false).map(KEY_NAME).distinct().count()).intValue();
         if (this.maxMatches == 0 || maxResults == 0) {
             throw new DissectException.PatternParse(pattern, "Unable to find any keys or delimiters.");
         }

libs/dissect/src/test/java/org/elasticsearch/dissect/DissectKeyTests.java

@@ -112,7 +112,7 @@ public void testRightPaddingModifiers() {
     public void testMultipleLeftModifiers() {
         String keyName = randomAlphaOfLengthBetween(1, 10);
         List<String> validModifiers = EnumSet.allOf(DissectKey.Modifier.class).stream()
-            .filter(m -> !m.equals(DissectKey.Modifier.NONE))
+            .filter(m -> m.equals(DissectKey.Modifier.NONE) == false)
             .map(DissectKey.Modifier::toString)
             .collect(Collectors.toList());
         String modifier1 = randomFrom(validModifiers);

libs/geo/src/main/java/org/elasticsearch/geometry/utils/Geohash.java

@@ -53,7 +53,7 @@ public class Geohash {
         for(int i = 1; i <= PRECISION; i++) {
             precisionToLatHeight[i] = precisionToLatHeight[i-1] / (even ? 8 : 4);
             precisionToLonWidth[i] = precisionToLonWidth[i-1] / (even ? 4 : 8);
-            even = ! even;
+            even = even == false;
         }
     }
 

libs/ssl-config/src/main/java/org/elasticsearch/common/ssl/SslClientAuthenticationMode.java

@@ -29,8 +29,8 @@ public boolean enabled() {
 
         public void configure(SSLParameters sslParameters) {
             // nothing to do here
-            assert !sslParameters.getWantClientAuth();
-            assert !sslParameters.getNeedClientAuth();
+            assert sslParameters.getWantClientAuth() == false;
+            assert sslParameters.getNeedClientAuth() == false;
         }
     },
     /**

libs/x-content/src/main/java/org/elasticsearch/common/xcontent/support/filtering/FilterPathBasedFilter.java

@@ -92,6 +92,6 @@ public TokenFilter includeProperty(String name) {
 
     @Override
     protected boolean _includeScalar() {
-        return !inclusive;
+        return inclusive == false;
     }
 }

server/src/main/java/org/elasticsearch/action/admin/cluster/snapshots/status/SnapshotIndexShardStatus.java

@@ -25,6 +25,7 @@
 import org.elasticsearch.index.snapshots.IndexShardSnapshotStatus;
 
 import java.io.IOException;
+import java.util.Objects;
 
 import static org.elasticsearch.common.xcontent.ConstructingObjectParser.constructorArg;
 import static org.elasticsearch.common.xcontent.ConstructingObjectParser.optionalConstructorArg;
@@ -199,15 +200,17 @@ public static SnapshotIndexShardStatus fromXContent(XContentParser parser, Strin
 
     @Override
     public boolean equals(Object o) {
-        if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
-
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
         SnapshotIndexShardStatus that = (SnapshotIndexShardStatus) o;
-
-        if (stage != that.stage) return false;
-        if (stats != null ? !stats.equals(that.stats) : that.stats != null) return false;
-        if (nodeId != null ? !nodeId.equals(that.nodeId) : that.nodeId != null) return false;
-        return failure != null ? failure.equals(that.failure) : that.failure == null;
+        return stage == that.stage
+            && Objects.equals(stats, that.stats)
+            && Objects.equals(nodeId, that.nodeId)
+            && Objects.equals(failure, that.failure);
     }
 
     @Override

server/src/main/java/org/elasticsearch/action/admin/cluster/snapshots/status/SnapshotIndexStatus.java

@@ -22,6 +22,7 @@
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 
 import static java.util.Collections.emptyMap;
 import static java.util.Collections.unmodifiableMap;
@@ -149,15 +150,17 @@ public static SnapshotIndexStatus fromXContent(XContentParser parser) throws IOE
 
     @Override
     public boolean equals(Object o) {
-        if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
-
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
         SnapshotIndexStatus that = (SnapshotIndexStatus) o;
-
-        if (index != null ? !index.equals(that.index) : that.index != null) return false;
-        if (indexShards != null ? !indexShards.equals(that.indexShards) : that.indexShards != null) return false;
-        if (shardsStats != null ? !shardsStats.equals(that.shardsStats) : that.shardsStats != null) return false;
-        return stats != null ? stats.equals(that.stats) : that.stats == null;
+        return Objects.equals(index, that.index)
+            && Objects.equals(indexShards, that.indexShards)
+            && Objects.equals(shardsStats, that.shardsStats)
+            && Objects.equals(stats, that.stats);
     }
 
     @Override

server/src/main/java/org/elasticsearch/action/admin/indices/alias/Alias.java

@@ -28,6 +28,7 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Map;
+import java.util.Objects;
 
 /**
  * Represents an alias, to be associated with an index
@@ -302,9 +303,7 @@ public boolean equals(Object o) {
 
         Alias alias = (Alias) o;
 
-        if (name != null ? !name.equals(alias.name) : alias.name != null) return false;
-
-        return true;
+        return Objects.equals(name, alias.name);
     }
 
     @Override

server/src/main/java/org/elasticsearch/action/admin/indices/analyze/AnalyzeAction.java

@@ -498,7 +498,7 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
             if (positionLength > 1) {
                 builder.field(POSITION_LENGTH, positionLength);
             }
-            if (attributes != null && !attributes.isEmpty()) {
+            if (attributes != null && attributes.isEmpty() == false) {
                 Map<String, Object> sortedAttributes = new TreeMap<>(attributes);
                 for (Map.Entry<String, Object> entity : sortedAttributes.entrySet()) {
                     builder.field(entity.getKey(), entity.getValue());

server/src/main/java/org/elasticsearch/action/admin/indices/stats/CommonStatsFlags.java

@@ -105,7 +105,7 @@ public CommonStatsFlags clear() {
     }
 
     public boolean anySet() {
-        return !flags.isEmpty();
+        return flags.isEmpty() == false;
     }
 
     public Flag[] getFlags() {

server/src/main/java/org/elasticsearch/action/admin/indices/template/get/GetIndexTemplatesRequest.java

@@ -49,7 +49,7 @@ public ActionRequestValidationException validate() {
             validationException = addValidationError("names is null or empty", validationException);
         } else {
             for (String name : names) {
-                if (name == null || !Strings.hasText(name)) {
+                if (name == null || Strings.hasText(name) == false) {
                     validationException = addValidationError("name is missing", validationException);
                 }
             }

server/src/main/java/org/elasticsearch/action/admin/indices/validate/query/ValidateQueryResponse.java

@@ -101,7 +101,7 @@ public void writeTo(StreamOutput out) throws IOException {
     @Override
     protected void addCustomXContentFields(XContentBuilder builder, Params params) throws IOException {
         builder.field(VALID_FIELD, isValid());
-        if (getQueryExplanation() != null && !getQueryExplanation().isEmpty()) {
+        if (getQueryExplanation() != null && getQueryExplanation().isEmpty() == false) {
             builder.startArray(EXPLANATIONS_FIELD);
             for (QueryExplanation explanation : getQueryExplanation()) {
                 builder.startObject();

server/src/main/java/org/elasticsearch/action/bulk/BulkRequest.java

@@ -464,14 +464,14 @@ private void applyGlobalMandatoryParameters(DocWriteRequest<?> request) {
     }
 
     private static String valueOrDefault(String value, String globalDefault) {
-        if (Strings.isNullOrEmpty(value) && !Strings.isNullOrEmpty(globalDefault)) {
+        if (Strings.isNullOrEmpty(value) && Strings.isNullOrEmpty(globalDefault) == false) {
             return globalDefault;
         }
         return value;
     }
 
     private static Boolean valueOrDefault(Boolean value, Boolean globalDefault) {
-        if (Objects.isNull(value) && !Objects.isNull(globalDefault)) {
+        if (Objects.isNull(value) && Objects.isNull(globalDefault) == false) {
             return globalDefault;
         }
         return value;

server/src/main/java/org/elasticsearch/action/bulk/Retry.java

@@ -97,7 +97,7 @@ public void onResponse(BulkResponse bulkItemResponses) {
                 finishHim();
             } else {
                 if (canRetry(bulkItemResponses)) {
-                    addResponses(bulkItemResponses, (r -> !r.isFailed()));
+                    addResponses(bulkItemResponses, (r -> r.isFailed() == false));
                     retry(createBulkRequestForRetry(bulkItemResponses));
                 } else {
                     addResponses(bulkItemResponses, (r -> true));

server/src/main/java/org/elasticsearch/action/get/TransportGetAction.java

@@ -88,7 +88,7 @@ protected GetResponse shardOperation(GetRequest request, ShardId shardId) {
         IndexService indexService = indicesService.indexServiceSafe(shardId.getIndex());
         IndexShard indexShard = indexService.getShard(shardId.id());
 
-        if (request.refresh() && !request.realtime()) {
+        if (request.refresh() && request.realtime() == false) {
             indexShard.refresh("refresh_flag_get");
         }
 

server/src/main/java/org/elasticsearch/action/get/TransportShardMultiGetAction.java

@@ -88,7 +88,7 @@ protected MultiGetShardResponse shardOperation(MultiGetShardRequest request, Sha
         IndexService indexService = indicesService.indexServiceSafe(shardId.getIndex());
         IndexShard indexShard = indexService.getShard(shardId.id());
 
-        if (request.refresh() && !request.realtime()) {
+        if (request.refresh() && request.realtime() == false) {
             indexShard.refresh("refresh_flag_mget");
         }
 

server/src/main/java/org/elasticsearch/action/ingest/GetPipelineResponse.java

@@ -64,7 +64,7 @@ public void writeTo(StreamOutput out) throws IOException {
     }
 
     public boolean isFound() {
-        return !pipelines.isEmpty();
+        return pipelines.isEmpty() == false;
     }
 
     @Override

server/src/main/java/org/elasticsearch/action/search/SearchPhaseController.java

@@ -97,7 +97,7 @@ public AggregatedDfs aggregateDfs(Collection<DfsSearchResult> results) {
 
             }
 
-            assert !lEntry.fieldStatistics().containsKey(null);
+            assert lEntry.fieldStatistics().containsKey(null) == false;
             final Object[] keys = lEntry.fieldStatistics().keys;
             final Object[] values = lEntry.fieldStatistics().values;
             for (int i = 0; i < keys.length; i++) {

server/src/main/java/org/elasticsearch/action/support/TransportActions.java

@@ -32,7 +32,7 @@ public static boolean isShardNotAvailableException(final Throwable e) {
      * If a failure is already present, should this failure override it or not for read operations.
      */
     public static boolean isReadOverrideException(Exception e) {
-        return !isShardNotAvailableException(e);
+        return isShardNotAvailableException(e) == false;
     }
 
 }

server/src/main/java/org/elasticsearch/action/support/broadcast/node/TransportBroadcastByNodeAction.java

@@ -352,7 +352,7 @@ protected void onNodeResponse(DiscoveryNode node, int nodeIndex, NodeResponse re
 
         protected void onNodeFailure(DiscoveryNode node, int nodeIndex, Throwable t) {
             String nodeId = node.getId();
-            if (logger.isDebugEnabled() && !(t instanceof NodeShouldNotConnectException)) {
+            if (logger.isDebugEnabled() && (t instanceof NodeShouldNotConnectException) == false) {
                 logger.debug(new ParameterizedMessage("failed to execute [{}] on node [{}]", actionName, nodeId), t);
             }
 

server/src/main/java/org/elasticsearch/action/support/master/TransportMasterNodeAction.java

@@ -133,7 +133,7 @@ protected void doStart(ClusterState clusterState) {
                             retry(clusterState, blockException, newState -> {
                                 try {
                                     ClusterBlockException newException = checkBlock(request, newState);
-                                    return (newException == null || !newException.retryable());
+                                    return (newException == null || newException.retryable() == false);
                                 } catch (Exception e) {
                                     // accept state as block will be rechecked by doStart() and listener.onFailure() then called
                                     logger.trace("exception occurred during cluster block checking, accepting state", e);

server/src/main/java/org/elasticsearch/action/support/nodes/TransportNodesAction.java

@@ -231,7 +231,7 @@ private void onOperation(int idx, NodeResponse nodeResponse) {
         }
 
         private void onFailure(int idx, String nodeId, Throwable t) {
-            if (logger.isDebugEnabled() && !(t instanceof NodeShouldNotConnectException)) {
+            if (logger.isDebugEnabled() && (t instanceof NodeShouldNotConnectException) == false) {
                 logger.debug(new ParameterizedMessage("failed to execute on node [{}]", nodeId), t);
             }
             responses.set(idx, new FailedNodeException(nodeId, "Failed node [" + nodeId + "]", t));

server/src/main/java/org/elasticsearch/action/support/tasks/TransportTasksAction.java

@@ -279,7 +279,7 @@ private void onOperation(int idx, NodeTasksResponse nodeResponse) {
         }
 
         private void onFailure(int idx, String nodeId, Throwable t) {
-            if (logger.isDebugEnabled() && !(t instanceof NodeShouldNotConnectException)) {
+            if (logger.isDebugEnabled() && (t instanceof NodeShouldNotConnectException) == false) {
                 logger.debug(new ParameterizedMessage("failed to execute on node [{}]", nodeId), t);
             }
 

server/src/main/java/org/elasticsearch/action/termvectors/TermVectorsRequest.java

@@ -502,7 +502,7 @@ private void setFlag(Flag flag, boolean set) {
             flagsEnum.add(flag);
         } else if (set == false) {
             flagsEnum.remove(flag);
-            assert (!flagsEnum.contains(flag));
+            assert flagsEnum.contains(flag) == false;
         }
     }
 

server/src/main/java/org/elasticsearch/action/termvectors/TermVectorsWriter.java

@@ -48,7 +48,7 @@ void setFields(Fields termVectorsByField, Set<String> selectedFields, EnumSet<Fl
         boolean hasScores = termVectorsFilter != null;
 
         for (String field : termVectorsByField) {
-            if ((selectedFields != null) && (!selectedFields.contains(field))) {
+            if (selectedFields != null && selectedFields.contains(field) == false) {
                 continue;
             }
 
@@ -85,7 +85,7 @@ void setFields(Fields termVectorsByField, Set<String> selectedFields, EnumSet<Fl
                 Term term = new Term(field, termBytesRef);
 
                 // with filtering we only keep the best terms
-                if (hasScores && !termVectorsFilter.hasScoreTerm(term)) {
+                if (hasScores && termVectorsFilter.hasScoreTerm(term) == false) {
                     continue;
                 }
 

server/src/main/java/org/elasticsearch/action/update/UpdateHelper.java

@@ -113,7 +113,7 @@ Tuple<UpdateOpType, Map<String, Object>> executeScriptedUpsert(Map<String, Objec
      * {@code IndexRequest} to be executed on the primary and replicas.
      */
     Result prepareUpsert(ShardId shardId, UpdateRequest request, final GetResult getResult, LongSupplier nowInMillis) {
-            if (request.upsertRequest() == null && !request.docAsUpsert()) {
+            if (request.upsertRequest() == null && request.docAsUpsert() == false) {
                 throw new DocumentMissingException(shardId, request.type(), request.id());
             }
             IndexRequest indexRequest = request.docAsUpsert() ? request.doc() : request.upsertRequest();
@@ -176,7 +176,7 @@ Result prepareUpdateIndexRequest(ShardId shardId, UpdateRequest request, GetResu
         final XContentType updateSourceContentType = sourceAndContent.v1();
         final Map<String, Object> updatedSourceAsMap = sourceAndContent.v2();
 
-        final boolean noop = !XContentHelper.update(updatedSourceAsMap, currentRequest.sourceAsMap(), detectNoop);
+        final boolean noop = XContentHelper.update(updatedSourceAsMap, currentRequest.sourceAsMap(), detectNoop) == false;
 
         // We can only actually turn the update into a noop if detectNoop is true to preserve backwards compatibility and to handle cases
         // where users repopulating multi-fields or adding synonyms, etc.

server/src/main/java/org/elasticsearch/bootstrap/BootstrapCheck.java

@@ -42,7 +42,7 @@ public boolean isSuccess() {
         }
 
         public boolean isFailure() {
-            return !isSuccess();
+            return isSuccess() == false;
         }
 
         public String getMessage() {

server/src/main/java/org/elasticsearch/bootstrap/BootstrapChecks.java

@@ -172,9 +172,9 @@ static void log(final Logger logger, final String error) {
     static boolean enforceLimits(final BoundTransportAddress boundTransportAddress, final String discoveryType) {
         final Predicate<TransportAddress> isLoopbackAddress = t -> t.address().getAddress().isLoopbackAddress();
         final boolean bound =
-                !(Arrays.stream(boundTransportAddress.boundAddresses()).allMatch(isLoopbackAddress) &&
-                isLoopbackAddress.test(boundTransportAddress.publishAddress()));
-        return bound && !"single-node".equals(discoveryType);
+                (Arrays.stream(boundTransportAddress.boundAddresses()).allMatch(isLoopbackAddress) &&
+                isLoopbackAddress.test(boundTransportAddress.publishAddress())) == false;
+        return bound && "single-node".equals(discoveryType) == false;
     }
 
     // the list of checks to execute
@@ -578,7 +578,7 @@ static class OnErrorCheck extends MightForkCheck {
         @Override
         boolean mightFork() {
             final String onError = onError();
-            return onError != null && !onError.equals("");
+            return onError != null && onError.isEmpty() == false;
         }
 
         // visible for testing
@@ -603,7 +603,7 @@ static class OnOutOfMemoryErrorCheck extends MightForkCheck {
         @Override
         boolean mightFork() {
             final String onOutOfMemoryError = onOutOfMemoryError();
-            return onOutOfMemoryError != null && !onOutOfMemoryError.equals("");
+            return onOutOfMemoryError != null && onOutOfMemoryError.isEmpty() == false;
         }
 
         // visible for testing

server/src/main/java/org/elasticsearch/bootstrap/Elasticsearch.java

@@ -156,7 +156,7 @@ protected void execute(Terminal terminal, OptionSet options, Environment env) th
     void init(final boolean daemonize, final Path pidFile, final boolean quiet, Environment initialEnv)
         throws NodeValidationException, UserException {
         try {
-            Bootstrap.init(!daemonize, pidFile, quiet, initialEnv);
+            Bootstrap.init(daemonize == false, pidFile, quiet, initialEnv);
         } catch (BootstrapException | RuntimeException e) {
             // format exceptions to the console in a special way
             // to avoid 2MB stacktraces from guice, etc.