public class SimpleDataStruct
extends java.lang.Object

It is not a final (able to expand) data class. It doesn't base on ObjectJc in C. In C the struct is defined as:

typedef struct ExpandableDataStruct_Test_t
{ 
  int16 xb;
  int16 yb;
  double db;
} ExpandableDataStruct_Test_s;

It is very simple. Such an class may be used in an array. The inheritance from Object is a basic feature in Java anytime, but this feature doesn't may be used mostly. Therefore in C it can be optimized writing a @ java2c=noObject.-tag in the comment.

See also ExpandedDataStruct. Inherited classes don't base on Object too.