HBase folks, I'd like to work on upgrading some of the dependencies in Hadoop that are starting to lag behind:
jackson2 (https://issues.apache.org/jira/browse/HADOOP-12705) jaxb-api (https://issues.apache.org/jira/browse/HADOOP-13659) commons-configuration (https://issues.apache.org/jira/browse/HADOOP-13660) htrace (https://issues.apache.org/jira/browse/HADOOP-13661) Some of these (chiefly jackson) are known to be high risk upgrades and have caused problems for HBase in the past. I wanted to give you a heads up about this work and coordinate with you to make sure I do all the testing you think is necessary to discover any potential problems well in advance of the breakages. I was going to look at just running HBase's unit tests when built against my Hadoop's trunk with my changes (Should I expect any problems here? Is there a branch already focused on Hadoop 3 compatibility or anything?) and Bigtop's integration tests too. Anything else you would add to this?
