Java: Rationale of the Object class not being declared abstract

Question

Why wasn\'t the java.lang.Object class declared to be abstract ?

Surely for an Object to be useful it needs added state or behaviour, an Object class is

Answer 1

As always, Guava comes to help: with http://docs.guava-libraries.googlecode.com/git/javadoc/com/google/common/base/Optional.html Stuff here can be used to kill nulls / Object instances for "a not-null placeholder" from the code.

There are entirely seperated questions here:

• why did not they make Object abstract?
• how much disaster comes after if they decide to make it abstract in a future release?