Remove Redundant ConcurrentHashMapLong (#76172) (#76524)

This class is nothing but a noop wrapper around a normal CHM.
It does nothing, adds indirection and hides the fact that it's just a
standard CHM and has all the same boxing/unboxing under the hood.

server/src/main/java/org/elasticsearch/common/util/concurrent/ConcurrentCollections.java

@@ -46,17 +46,6 @@ public static <K, V> ConcurrentMap<K, V> newConcurrentMap() {
         return new ConcurrentHashMap<>();
     }
 
-    /**
-     * Creates a new CHM with an aggressive concurrency level, aimed at highly updateable long living maps.
-     */
-    public static <V> ConcurrentMapLong<V> newConcurrentMapLongWithAggressiveConcurrency() {
-        return new ConcurrentHashMapLong<>(ConcurrentCollections.<Long, V>newConcurrentMapWithAggressiveConcurrency());
-    }
-
-    public static <V> ConcurrentMapLong<V> newConcurrentMapLong() {
-        return new ConcurrentHashMapLong<>(ConcurrentCollections.<Long, V>newConcurrentMap());
-    }
-
     public static <V> Set<V> newConcurrentSet() {
         return Collections.newSetFromMap(ConcurrentCollections.<V, Boolean>newConcurrentMap());
     }

server/src/main/java/org/elasticsearch/search/SearchService.java

@@ -43,7 +43,6 @@
 import org.elasticsearch.common.util.BigArrays;
 import org.elasticsearch.common.util.CollectionUtils;
 import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
-import org.elasticsearch.common.util.concurrent.ConcurrentMapLong;
 import org.elasticsearch.core.internal.io.IOUtils;
 import org.elasticsearch.index.Index;
 import org.elasticsearch.index.IndexNotFoundException;
@@ -221,7 +220,7 @@ public class SearchService extends AbstractLifecycleComponent implements IndexEv
 
     private final AtomicLong idGenerator = new AtomicLong();
 
-    private final ConcurrentMapLong<ReaderContext> activeReaders = ConcurrentCollections.newConcurrentMapLongWithAggressiveConcurrency();
+    private final Map<Long, ReaderContext> activeReaders = ConcurrentCollections.newConcurrentMapWithAggressiveConcurrency();
 
     private final MultiBucketConsumerService multiBucketConsumerService;
 

server/src/main/java/org/elasticsearch/tasks/TaskManager.java

@@ -32,7 +32,6 @@
 import org.elasticsearch.core.TimeValue;
 import org.elasticsearch.common.util.concurrent.AbstractRunnable;
 import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
-import org.elasticsearch.common.util.concurrent.ConcurrentMapLong;
 import org.elasticsearch.common.util.concurrent.ThreadContext;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.transport.TaskTransportChannel;
@@ -77,7 +76,7 @@ public class TaskManager implements ClusterStateApplier {
     private final List<String> taskHeaders;
     private final ThreadPool threadPool;
 
-    private final ConcurrentMapLong<Task> tasks = ConcurrentCollections.newConcurrentMapLongWithAggressiveConcurrency();
+    private final Map<Long, Task> tasks = ConcurrentCollections.newConcurrentMapWithAggressiveConcurrency();
 
     private final CancellableTasksTracker<CancellableTaskHolder> cancellableTasks
         = new CancellableTasksTracker<>(new CancellableTaskHolder[0]);

server/src/main/java/org/elasticsearch/transport/Transport.java

@@ -17,7 +17,6 @@
 import org.elasticsearch.common.transport.TransportAddress;
 import org.elasticsearch.core.TimeValue;
 import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
-import org.elasticsearch.common.util.concurrent.ConcurrentMapLong;
 
 import java.io.Closeable;
 import java.io.IOException;
@@ -165,8 +164,8 @@ public String action() {
      * This class is a registry that allows
      */
     final class ResponseHandlers {
-        private final ConcurrentMapLong<ResponseContext<? extends TransportResponse>> handlers = ConcurrentCollections
-            .newConcurrentMapLongWithAggressiveConcurrency();
+        private final Map<Long, ResponseContext<? extends TransportResponse>> handlers = ConcurrentCollections
+            .newConcurrentMapWithAggressiveConcurrency();
         private final AtomicLong requestIdGenerator = new AtomicLong();
 
         /**

x-pack/plugin/ml/qa/native-multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/ml/integration/DatafeedJobsIT.java

@@ -19,7 +19,6 @@
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.core.TimeValue;
 import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
-import org.elasticsearch.common.util.concurrent.ConcurrentMapLong;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.search.SearchHits;
 import org.elasticsearch.search.aggregations.AggregationBuilders;
@@ -615,7 +614,7 @@ public void testRealtime_multipleStopCalls() throws Exception {
         final String datafeedId = jobId + "-datafeed";
         startRealtime(jobId);
 
-        ConcurrentMapLong<AssertionError> exceptions = ConcurrentCollections.newConcurrentMapLong();
+        Map<Long, AssertionError> exceptions = ConcurrentCollections.newConcurrentMap();
 
         // It's practically impossible to assert that a stop request has waited
         // for a concurrently executing request to finish before returning.

x-pack/plugin/ml/qa/native-multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/ml/integration/MlJobIT.java

@@ -725,8 +725,8 @@ public void testDelete_multipleRequest() throws Exception {
         String jobId = "delete-job-multiple-times";
         createFarequoteJob(jobId);
 
-        ConcurrentMapLong<Response> responses = ConcurrentCollections.newConcurrentMapLong();
-        ConcurrentMapLong<ResponseException> responseExceptions = ConcurrentCollections.newConcurrentMapLong();
+        Map<Long, Response> responses = ConcurrentCollections.newConcurrentMap();
+        Map<Long, ResponseException> responseExceptions = ConcurrentCollections.newConcurrentMap();
         AtomicReference<IOException> ioe = new AtomicReference<>();
         AtomicInteger recreationGuard = new AtomicInteger(0);
         AtomicReference<Response> recreationResponse = new AtomicReference<>();