Oracle Database Express Edition (XE)

I want to do something like this.

DECLARE

    v_jason_table   json_array_t;

BEGIN

    SELECT

        JSON_OBJECT(

            'role_id' IS role_id,

            'role_name' IS role_name,

            'role_index' IS role_index,

            'role_create_date' IS TO_CHAR(role_create_date, 'DD-MON-YYYY')

        )

    INTO v_jason_table

    FROM

        member_roles;

END;

Is this possible?

Thanks