The use of long for this value is deliberate because of the lack of unsigned integer values in the Java
language. GlueGen automatically picks the next larger type when the sign bit is set, as in this value. I
don't remember exactly when we made the change to GlueGen but I am pretty sure it was motivated by
incorrect glue code generation for some set of C APIs, possibly OpenGL APIs. There is no plan to change
this unless there is a strong reason to do so.