public Set<ServerName> getSplittingServersFromWALDir() throws IOException {
    return getServerNamesFromWALDirPath(
      p -> p.getName().endsWith(AbstractFSWALProvider.SPLITTING_EXT));
  }
Get Servernames which are currently splitting; paths have a '-splitting' suffix.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/MasterWalManager.java