demote : Java Glossary

You might want to demote an object to strip off unnecessary fields for transport or long term storage. You might want to demote it to remove confidential or unnecessary information before handing it off to someone else. You might want to strip off set methods to make the object immutable.

To demote an object in Java, you need copy Dalmatian copy constructor that takes a Dog parameter. Internally it must copy field by field. It might be implemented very slowly with reflection. It might be possible to implement it with JNI (Java Native Interface) that was more aware than usual of the platform specific implementation. If promoting were built into Java, it could be implemented with a block move.