How to use constructor to create a null object?

I am trying to extend java.sql.Timestamp class. However, I am not sure what to do with a null Timestamp object. The constructor of Timestamp always creates a valid Timestamp object. Anyone have any idea how to create a null object using constructor? Thanks.
Julia

when you create an object i.e., instantiate an object there are three steps that are followed behind the scene.
1) Assign memory
2) Allocate a reference
3) constructor is called.
Now there is no such thing as a null object as has been pointed out however in case you mean you just want to assign a null reference to a variable then you are not instantiating an object and not calling a constructor but you could simply do
String sqlQuery = null;But keep in mind that the object has not been instantiated and neither initialized here. Constructors basically do the initialization.

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    null
    Message was edited by:
            Ameya Pimpalgaonkar

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