Can you build an object without calling its constructor?

Actually, you can. The Java language is designed so that calling a constructor is the only way to create an object. Of course, you can create factory methods that you call from your application code, so that the constructor call does not appear in that code. But that factory method still calls a constructor internally. This is how Java was designed from the beginning.

There is one exception to that: serialization. When you deserialize an object, the deserialization mechanism does not call the constructor of that object. It bypasses it, which is actually a security issue: if you have validation rules in your constructor, they get bypassed by the deserialization mechanism, allowing a corrupted object to live in your application.

Records were created after serialization was implemented, and they are an exception to the exception. Deserialization does call your record's canonical constructor and its validation rules. There is no way to create a record without calling its canonical constructor. One more reason to use them wherever you can.