DFSClient may read wrong data in local read

[jlei liu]

In local read, BlockReaderLocal class use "static Map<Integer,
LocalDatanodeInfo> localDatanodeInfoMap" property to store local block file
path and local meta file path. When I stop HDFS cluster or I kill the local
DataNode and delete file use "./hadoop dfs -rm path" command , the
DFSClient still can read the data form local file. I think that may lead to
DFSClient read wrong data.

I think we should fix the problem.


Thanks,

LiuLei