Let’s summarize this chapter:
nullis the value indicating that a variable does not provide access to any value.
References that have the
nullvalue can only be used in two operations: assigning a value to them and determining whether they are
==operator may have to access an actual object, determining whether a variable is
nullmust be performed by the
!isis the opposite of
nullto a variable makes that variable provide access to nothing.
Objects that are not referenced by any variable are finalized by the garbage collector.