Check the Session accessing objects

SELECT /* + RULE */ LS.OSUSER OS_USER_NAME, LS.USERNAME USER_NAME,
DECODE (LS.TYPE, 'RW', 'ROW WAIT ENQUEUE LOCK', 'TM', 'DML ENQUEUE LOCK', 'TX',
'TRANSACTION ENQUEUE LOCK', 'UL', 'USER SUPPLIED LOCK') LOCK_TYPE,
O.OBJECT_NAME OBJECT, DECODE (LS.LMODE, 1, NULL, 2, 'ROW SHARE', 3,
'ROW EXCLUSIVE', 4, 'SHARE', 5, 'SHARE ROW EXCLUSIVE', 6, 'EXCLUSIVE', NULL)
LOCK_MODE, O.OWNER, LS.SID, LS.SERIAL# SERIAL_NUM, LS.ID1, LS.ID2
FROM SYS.DBA_OBJECTS O, (SELECT S.OSUSER, S.USERNAME, L.TYPE,
L.LMODE, S.SID, S.SERIAL#, L.ID1, L.ID2 FROM V$SESSION S,
V$LOCK L WHERE S.SID = L.SID) LS WHERE O.OBJECT_ID = LS.ID1 AND O.OWNER
<> 'SYS' ORDER BY O.OWNER, O.OBJECT_NAME