Address other comments

Author: mccheah

core/src/main/java/org/apache/spark/shuffle/sort/io/LocalDiskShuffleExecutorComponents.java

@@ -17,9 +17,10 @@
 
 package org.apache.spark.shuffle.sort.io;
 
+import java.util.Optional;
+
 import com.google.common.annotations.VisibleForTesting;
 
-import java.util.Optional;
 import org.apache.spark.SparkConf;
 import org.apache.spark.SparkEnv;
 import org.apache.spark.shuffle.api.ShuffleExecutorComponents;

core/src/main/java/org/apache/spark/shuffle/sort/io/LocalDiskShuffleMapOutputWriter.java

@@ -138,8 +138,6 @@ private void cleanUp() throws IOException {
 
   private void initStream() throws IOException {
     if (outputFileStream == null) {
-      // This file needs to opened in append mode in order to work around a Linux kernel bug that
-      // affects transferTo; see SPARK-3948 for more details.
       outputFileStream = new FileOutputStream(outputTempFile, true);
     }
     if (outputBufferedFileStream == null) {
@@ -148,11 +146,10 @@ private void initStream() throws IOException {
   }
 
   private void initChannel() throws IOException {
-    if (outputFileStream == null) {
-      outputFileStream = new FileOutputStream(outputTempFile, true);
-    }
+    // This file needs to opened in append mode in order to work around a Linux kernel bug that
+    // affects transferTo; see SPARK-3948 for more details.
     if (outputFileChannel == null) {
-      outputFileChannel = outputFileStream.getChannel();
+      outputFileChannel = new FileOutputStream(outputTempFile, true).getChannel();
     }
   }