you can get reports from oracle db by your java app.

App can get below error and you can see DROPPED packages at Oracle DB server OS.

Solutions are ; 

- report SQL performance improvement because long running bad sql can cause it
- or you may prefer using JNDI instead of JDBC/THIN and use below parameter:
  SQLNET.SEND_TIMEOUT=3600


java.sql.SQLException: ORA-12592: TNS:bad packet

ens3f0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        ether 48:df:37:52:db:d0  txqueuelen 1000  (Ethernet)
        RX packets 3071038398  bytes 2110435413132 (1.9 TiB)
        RX errors 0  dropped 1119  overruns 0  frame 0