HttpSession constructor Null safety

1. Dart
2. dart:io
3. HttpSession
4. HttpSession constructor

HttpSession class

1. Constructors
2. HttpSession
3. Properties
4. entries
5. hashCode
6. id
7. isEmpty
8. isNew
9. isNotEmpty
10. keys
11. length
12. onTimeout
13. runtimeType
14. values
15. Methods
16. addAll
17. addEntries
18. cast
19. clear
20. containsKey
21. containsValue
22. destroy
23. forEach
24. map
25. noSuchMethod
26. putIfAbsent
27. remove
28. removeWhere
29. toString
30. update
31. updateAll
32. Operators
33. operator ==
34. operator []
35. operator []=