Cancel object creation in beforeSave (of business logic)

To prevent duplicate data, I need to check if a similar object exists in the beforeSave of my custom class.

How can I tell it to cancel creating the object in beforeSave if the certain conditions are met?

In plain english, it would look something like:

if (similar object already exists) {
     don't go through with creating this object

Right now you can throw an exception and should stop further execution of the API request. Soon there will be additional controls for how errors are returned back to the client from custom business logic.


Can I throw exception in beforeCreate also to abort object creation