How can I make use of C# System.DBNull.value in Java?
 I'm translating some code written in C# to Java.  This code uses COM objects to interact with a third party application.  I managed to handle COM objects using com4j library, but one of the methods requires System.DBNull.value to be passed into it which is a C# object.  
How can I handle it from a Java application?
 .NET System.DBNull is equivalent to a VARIANT of type VT_NULL.  In fact this is documented officially here: DBNull Class  
So I suppose using com4j you can create a Variant, call setType(VT_NULL), and pass this to the .NET interop layer.
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