[typo] Fix many typos and optimize some code

Author: zcoo

fluss-server/src/main/java/org/apache/fluss/server/coordinator/CoordinatorEventProcessor.java

@@ -1005,7 +1005,7 @@ private void processNewTabletServer(NewTabletServerEvent newTabletServerEvent) {
             // it may happen during coordinator server initiation, the watcher watch a new tablet
             // server register event and put it to event manager, but after that, the coordinator
             // server read
-            // all tablet server nodes registered which contain the tablet server a; in this case,
+            // all tablet server nodes registered which contain the tablet server; in this case,
             // we can ignore it.
             return;
         }
@@ -1398,7 +1398,7 @@ private void tryToCompleteRebalanceTask(TableBucket tableBucket) {
      *
      * <ul>
      *   <li>B1. Move all replicas in AR to OnlineReplica state.
-     *   <li>B2. Send a LeaderAndIsr request with RS = ORS +TRS. The will make the origin leader
+     *   <li>B2. Send a LeaderAndIsr request with RS = ORS +TRS. This will make the origin leader
      *       change to the new leader. this request will be sent to every tabletServer in ORS +TRS.
      *   <li>B3. Set RS = TRS, AR = [], RR = [] in memory.
      *   <li>Re-send LeaderAndIsr request with new leader and a new RS (using TRS) and same isr to
@@ -1408,7 +1408,7 @@ private void tryToCompleteRebalanceTask(TableBucket tableBucket) {
      *       Leader to notify it of the shrunk isr. After that, we send a StopReplica (delete =
      *       false and deleteRemote = false) to the replicas in RR.
      *   <li>B6. Move all replicas in RR to ReplicaMigrationStarted state. This will send a
-     *       StopReplica (delete = true and deleteRemote = false) to he replicas in RR to physically
+     *       StopReplica (delete = true and deleteRemote = false) to the replicas in RR to physically
      *       delete the replicas on disk but don't delete the data in remote storage.
      *   <li>B7. Update ZK with RS=TRS, AR=[], RR=[].
      *   <li>B8. After electing leader, the replicas and isr information changes. So resend the

fluss-server/src/main/java/org/apache/fluss/server/coordinator/CoordinatorRequestBatch.java

@@ -276,11 +276,11 @@ public void addStopReplicaRequestForTabletServers(
      *       none-partitioned table
      *   <li>case3: Table create and bucketAssignment don't generated, case will happen for new
      *       created partitioned table
-     *   <li>case4: Table is queued for deletion, in this case we will set a empty tableBucket set
+     *   <li>case4: Table is queued for deletion, in this case we will set an empty tableBucket set
      *       and tableId set to {@link TableMetadata#DELETED_TABLE_ID} to avoid send unless info to
      *       tabletServer
      *   <li>case5: Partition create and bucketAssignment of this partition generated.
-     *   <li>case6: Partition is queued for deletion, in this case we will set a empty tableBucket
+     *   <li>case6: Partition is queued for deletion, in this case we will set an empty tableBucket
      *       set and partitionId set to {@link PartitionMetadata#DELETED_PARTITION_ID } to avoid
      *       send unless info to tabletServer
      *   <li>case7: Leader and isr is changed for these input tableBuckets

fluss-server/src/main/java/org/apache/fluss/server/metrics/group/TableMetricGroup.java

@@ -33,7 +33,6 @@
 import javax.annotation.Nullable;
 
 import java.util.Map;
-import java.util.Objects;
 import java.util.stream.Stream;
 
 import static org.apache.fluss.metrics.utils.MetricGroupUtils.makeScope;
@@ -267,7 +266,7 @@ public java.util.Collection<BucketMetricGroup> getBucketMetricGroups() {
     public Stream<RocksDBStatistics> allRocksDBStatistics() {
         return buckets.values().stream()
                 .map(BucketMetricGroup::getRocksDBStatistics)
-                .filter(Objects::nonNull);
+                .filter(stats -> stats != null);
     }
 
     public TabletServerMetricGroup getServerMetricGroup() {

website/blog/2025-06-01-partial-updates.md

@@ -45,7 +45,7 @@ Next, let's try and better understand how this works in practice with a concrete
 ### Example: Building a Unified Wide Table
 > You can find the full source code on github [here](https://github.com/ververica/ververica-fluss-examples/tree/main/partial_updates).
 
-Start by cloning the repository, run `docker compose up` to spin up the development enviroment and finally grab a terminal 
+Start by cloning the repository, run `docker compose up` to spin up the development environment and finally grab a terminal 
 into the `jobmanager` and start the Flink SQL cli, by running the following command:
 ```shell
 ./bin/sql-client.sh
@@ -149,7 +149,7 @@ and then run:
 ```sql
 SELECT * FROM user_rec_wide;
 ```
-to observe the output of the table, as we insert `partially` records into the it from the different sources.
+to observe the output of the table, as we insert `partially` records into it from the different sources.
 
 **Step 5:** Let's insert the records from the `recommendations` table into the `user_rec_wide` table.
 ```sql

website/community/how-to-contribute/contribute-code.md

@@ -28,7 +28,7 @@ Create an issue and reach consensus.
 
 ### Implement
 
-Implement the change according to the Code Style and Quality(refer to the [Flink doc](https://flink.apache.org/how-to-contribute/code-style-and-quality-preamble/) Guide and the approach agreed upon in the issue.
+Implement the change according to the Code Style and Quality (refer to the [Flink doc](https://flink.apache.org/how-to-contribute/code-style-and-quality-preamble/) Guide and the approach agreed upon in the issue).
 
 1. Only start working on the implementation if there is consensus on the approach (e.g. you are assigned to the ticket)
 2. If you are newer, can refer to [ide setup](/community/dev/ide-setup) to setup a Fluss dev environment.

website/docs/maintenance/filesystems/oss.md

@@ -12,7 +12,7 @@ sidebar_position: 3
 
 ## Configurations setup
 
-To enabled OSS as remote storage, there are some required configurations that must be add to Fluss' `server.yaml`:
+To enabled OSS as remote storage, there are some required configurations that must be added to Fluss' `server.yaml`:
 
 ```yaml
 # The dir that used to be as the remote storage of Fluss