java.lang.ClassNotFo​undException: oracle.jdbc.driver.O​racleDriver

I am using Oracle 12c to test migration from Oracle to PostgreSQL. I am
using windows OS. I have copied ojdbc7.jar file under lib folder of
"EnterpriseDB-MigrationToolkit"

I am getting following error:

E:\sandeep\postgres\EnterpriseDB-MigrationToolkit>runMTK.bat -verbose on
-source
dbtype "oracle" @//localhost:1521/pdbsales.igatecorp.com
Source database connectivity info...
conn =jdbc:oracle:thin:@//localhost:1521/pdbsales.igatecorp.com
user =scott_name
password=******
Target database connectivity info...
conn =jdbc:postgresql://localhost:5432/postgres
user =postgres
password=******
Connecting with source Oracle database server...
Error: java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver

One or more schema objects could not be imported during the migration
process. P
lease review the migration output for more details.

Migration logs have been saved to
C:\Users\gondhasa.IGATECORP\.enterprisedb\migr
ation-toolkit\logs

******************** Migration Summary ********************

Total objects: 0
Successful count: 0
Failure count: 0