This is both a general question about java EOF exceptions, as well as Hadoop\'s EOF exception which is related to jar interoperability. Comments and answers on either topic
Regarding hadoop : I fixed the error ! You need to make sure the core-site.xml is serving to 0.0.0.0 instead of 127.0.0.1(localhost).
If you get the EOF exception, it means that the port is not accessible externally on that ip, so there is no data to read between the hadoop client / server ipc.
EOFException on a socket means there's no more data and the peer has closed the connection.