Class Book
{
    String name;
    String id;
}

Class Book
{
    String name;
    String id;
    String xyzTitle;
    int abcNumberOfPages;
    float abcHeight;
    float abcWidth;
}

Class XYZBookInfo
{
   String title;
}

Class ABCBookInfo
{
   int numberOfPages;
   float height;
   float width;
}

Class Book
{
   String name;
   String id;
   XYZBookInfo xyzInfo;
   ABCBookInfo abcInfo;
}