https://hadoop.apache.org/docs/r2.7.3/api/org/apache/hadoop/contrib/bkjournal/package-summary.html
org.apache.hadoop.contrib.bkjournal (Apache Hadoop Main 2.7.3 API)
apache hadoopcontribmainapi
https://hadoop.apache.org/docs/r2.7.6/api/org/apache/hadoop/contrib/bkjournal/package-summary.html
org.apache.hadoop.contrib.bkjournal (Apache Hadoop Main 2.7.6 API)
apache hadoopcontribmainapi