More comments

Signed-off-by: Suraj Singh <[email protected]>

server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationIT.java

@@ -1260,7 +1260,7 @@ public void testPrimaryReceivesDocsDuringReplicaRecovery() throws Exception {
     }
 
     /**
-     * This test validates that that segment replications works for any random compression mode
+     * This test validates that segment replications works with random compression mode
      * @throws Exception
      */
     public void testCodecWithDifferentCompressionModes() throws Exception {
@@ -1349,18 +1349,18 @@ public void testCodecWithOlderCodecs() throws Exception {
     // Return oldest lucene codec name. It does this by iterating throw all directories under lucene library and filter
     // ones matching lucene codec name regex
     private String getOlderLuceneCodec() throws IOException {
-        TreeSet<String> codecNames = new TreeSet<>();
+        final TreeSet<String> codecNames = new TreeSet<>();
         ZipInputStream zip = new ZipInputStream(Codec.class.getProtectionDomain().getCodeSource().getLocation().openStream());
         Pattern pattern = Pattern.compile("lucene[0-9]+");
         while (true) {
             ZipEntry e = zip.getNextEntry();
             if (e == null) break;
             // Filter lucene codec names from directory
             if (e.isDirectory()) {
-                // Remove trailing `/` file separator
+                // Remove trailing file separator from path i.e. '../lucene94/' -> '../lucene94'
                 final String dirPath = e.getName().substring(0, e.getName().length() - 1);
-                int index = dirPath.lastIndexOf(File.separator);
-                final String dirName = dirPath.substring(index + 1);
+                // Fetch name i.e. '../lucene94' -> 'lucene94'
+                final String dirName = dirPath.substring(dirPath.lastIndexOf(File.separator) + 1);
                 Matcher matcher = pattern.matcher(dirName);
                 if (matcher.matches()) {
                     codecNames.add(dirName);