This provides the flexibility in type system design to map nullobjects to their corresponding XML types.
这就为类型系统设计提供了将空(null)对象映射为其对应的xml类型的灵活性。
2
In addition, avoid returning objects that are null or in an invalid state.
此外,避免返回空对象或者状态无效的对象。
3
Weakly-typed collection objects, arrays containing null elements, and certain native data types all pose special problems for interoperability. Specifically