Query to check for Table Locks

#########################
TO CHECK FOR TABLE LOCKS
#########################
set pagesize 400
set linesize 600
col USERNAME for a15
col OS_USER_NAME for a15
col TERMINAL for a15
col OBJECT_NAME for a30
SELECT a.sid,a.serial#, a.username,c.os_user_name,a.terminal, b.object_id,substr(b.object_name,1,40) object_name
from v$session a, dba_objects b, v$locked_object c where a.sid = c.session_id and b.object_id = c.object_id;