diff --git a/clients/src/main/java/org/apache/kafka/clients/admin/KafkaAdminClient.java b/clients/src/main/java/org/apache/kafka/clients/admin/KafkaAdminClient.java
index ec896ca6d6422..f62e3b714813b 100644
--- a/clients/src/main/java/org/apache/kafka/clients/admin/KafkaAdminClient.java
+++ b/clients/src/main/java/org/apache/kafka/clients/admin/KafkaAdminClient.java
@@ -2242,10 +2242,9 @@ public DescribeReplicaLogDirsResult describeReplicaLogDirs(Collection<TopicParti
 
         Map<Integer, Set<TopicPartition>> partitionsByBroker = new HashMap<>();
 
-        for (TopicPartitionReplica replica: replicas) {
-            if (!partitionsByBroker.containsKey(replica.brokerId()))
-                partitionsByBroker.put(replica.brokerId(), new HashSet<>());
-            partitionsByBroker.get(replica.brokerId()).add(new TopicPartition(replica.topic(), replica.partition()));
+        for (TopicPartitionReplica replica : replicas) {
+            partitionsByBroker.computeIfAbsent(replica.brokerId(), key -> new HashSet<>())
+                .add(new TopicPartition(replica.topic(), replica.partition()));
         }
 
         final long now = time.milliseconds();
@@ -2414,9 +2413,8 @@ void handleResponse(AbstractResponse abstractResponse) {
                     } else {
                         Node node = cluster.leaderFor(entry.getKey());
                         if (node != null) {
-                            if (!leaders.containsKey(node))
-                                leaders.put(node, new HashMap<>());
-                            leaders.get(node).put(entry.getKey(), entry.getValue().beforeOffset());
+                            leaders.computeIfAbsent(node, key -> new HashMap<>()).put(entry.getKey(),
+                                entry.getValue().beforeOffset());
                         } else {
                             future.completeExceptionally(Errors.LEADER_NOT_AVAILABLE.exception());
                         }
diff --git a/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/distributed/ConnectProtocol.java b/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/distributed/ConnectProtocol.java
index 15fc6059a627b..c167e80991fe5 100644
--- a/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/distributed/ConnectProtocol.java
+++ b/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/distributed/ConnectProtocol.java
@@ -387,21 +387,11 @@ protected Map<String, Collection<Integer>> asMap() {
             // Using LinkedHashMap preserves the ordering, which is helpful for tests and debugging
             Map<String, Collection<Integer>> taskMap = new LinkedHashMap<>();
             for (String connectorId : new HashSet<>(connectorIds)) {
-                Collection<Integer> connectorTasks = taskMap.get(connectorId);
-                if (connectorTasks == null) {
-                    connectorTasks = new ArrayList<>();
-                    taskMap.put(connectorId, connectorTasks);
-                }
-                connectorTasks.add(CONNECTOR_TASK);
+                taskMap.computeIfAbsent(connectorId, key -> new ArrayList<>()).add(CONNECTOR_TASK);
             }
             for (ConnectorTaskId taskId : taskIds) {
                 String connectorId = taskId.connector();
-                Collection<Integer> connectorTasks = taskMap.get(connectorId);
-                if (connectorTasks == null) {
-                    connectorTasks = new ArrayList<>();
-                    taskMap.put(connectorId, connectorTasks);
-                }
-                connectorTasks.add(taskId.task());
+                taskMap.computeIfAbsent(connectorId, key -> new ArrayList<>()).add(taskId.task());
             }
             return taskMap;
         }