DataNode should be marked as final to prevent subclassing
---------------------------------------------------------
Key: HADOOP-3360
URL: https://issues.apache.org/jira/browse/HADOOP-3360
Project: Hadoop Core
Issue Type: Bug
Components: dfs
Affects Versions: 0.16.3
Reporter: Steve Loughran
Priority: Minor
Reviewing the DataNode core, it starts a thread in its constructor calling back
in to the Run() method. This is generally perceived as very dangerous, as if
DataNode were ever subclassed, the subclass would start to be invoked in the
run() method before its own constructor had finished working.
1. Consider splitting the constructor from the start() operation.
2. If this cannot be changed, mark DataNode as final so nobody can subclass it.
Though if the latter were done, it would be convenient to have a method to let
external management components poll for the health of the node, and to pick up
reasons for the node shutting down.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
