When use consistency validation check in BOPF, how to prevent the data being saved?

Hello,

When use consistency validation check in BOPF, how to prevent the data being saved?

In help document link:Validation - Business Object Metadata Model - SAP Library

if there are inconsistent node instances, a consistency validation behaves in one of the following ways:

• The validation sends messages to the consumer
• The validation sends messages to the consumer and prevents the transaction from being saved until the inconsistency is corrected
• The validation sends messages to the consumer and changes the consistency status.

I created a test class, but the data still be saved as the first way. How to implement the class like the second way?

Thank you.