OBAPI provides out of box business policies for all services. If only a part of the validation is to be modified or a new validation is to be added in addition to the validations that the existing business policy does, then it is possible to extend existing business policy and override existing validation.

Please note that this capability depends on how the original business policy is coded. If the out of box business performs all its validations in validatePolicy() method, then this approach may not be useful. On the other hand, if the out of box business policy has separate individual methods for validations and validatePolicy() method calls these methods one by one, then extension of the business policy is useful.

As we are creating a new business policy extending the existing business policy, it is also required to note that if the existing business policy needs to be suppressed and new business policy should work for a particular service then steps mentioned in earlier section for suppressing a business policy should be followed.

The steps to be followed as same as mentioned in earlier section, except the difference that the custom business policy class will extend the out of box business policy class and override its methods as per the requirement.