How to use optimistic locking in procedure?

I implemented an optimistic lock with a trigger, how can I do it without a trigger within procedure?

Can you write me an example "optimistic locking" with the procedure?

he most effective method to utilize hopeful securing Procedure upd_account, or I should utilize it in some other way

I do this as an activity, in the assignment it is composed that I focus on different use by the client, that more clients can change esteems for the equivalent acc_id. furthermore, to look hopeful versus negative locking and predictable read.

I can not discover anything about steady read. Is it related with hopeful locking? how to utilize reliable read? (or then again to make another inquiry)

I'm a tenderfoot in Oracle

I am sad on the off chance that I didn't clarify well.

I am work in prophet 12c discharge 2

Much thanks to you advance

I have bundle body and it resemble this:
CREATE OR REPLACE PACKAGE BODY account_api AS

...

PROCEDURE upd_account
(p_acc_id accounts.acc_id%type
, p_acc_name accounts.acc_name%type
, p_acc_amount accounts.acc_amount%type
, p_acc_date accounts.acc_date%type
)
IS
BEGIN
UPDATE accounts
set acc_name = p_acc_name
, acc_amount = p_acc_amount
, acc_date = p_acc_date
WHERE acc_id = p_acc_id;
COMMIT;
END;
...

end account_api;
/