Use Notes Objects in Java and more Java tips

1. Use Notes objects in memory and
other useful Java tips for XPages
development
Frank van der Linden

2. Me
• Java/XPages/Web/Domino developer
• Self employed at elstar IT
• OpenNTF director
• Speak at several national and international
events
• IBM Champion 2013 and 2014
• Live in the Netherlands
• Work everywhere
@flinden68
http://nl.linkedin.com/in/flinden68
flinden68@elstarit.nl
http://www.elstarit.nl

3. Disclaimer
All the code and the demos in this session will use the Java Notes
Objects which are part of the IBM/Lotus Notes product.
For a modern way of Java coding with Notes Objects please use the
OpenNTF Domino API.
Or even better use OpenNTF essentials

4. Roadmap
• Notes objects in memory
• Use of JSON
• MVC/Managed beans
• Java tip for XPages
• Date checks
• Utility class
• Extending classes
• Unit test
• Finally
• Some bonus code

5. Notes objects in memory

6. Bad practice
• Notes objects are not serializable
• Will not recycled the Java way, it will keep a pointer to the C object
• Can cause out of memory

7. What is serialization

8. XPages Java doc to the rescue

9. Put Notes document in memory
• Get Notesdocument
• Wrap Notesdocument into a DominoDocument

10. Get field values
• First check if document isRecycled
• Access field

11. On a XPage and more
• In a computed field
• In an edit box
• Update the backend document

12. Demo

13. What about attachments
• Get easy access to your attachments

14. What about attachments
• No calculation of paths
• Works both in XPinc and Web
• Call the attachment URL

15. Demo

16. Use build-in JSON classes

17. JSON building classes
• Part of the Extensibility API, since 8.5.2
• Easy way to build JSON

18. JSON building classes
• No concatenation of Strings
• Faster
• Readable code

19. MVC

20. MVC

21. MVC for XPages
• Separation of responsibility
• Cleaner code
• Easier to maintain
• Model = documents
• View = XPage
• Controller = Java managed bean

22. Managed beans

23. The requirements
• Needs to be Serializable
• At least one constructor without parameters
• Needs to be registrated in the Faces-config.xml
• Properties are private
• And have Getters and Setters

24. Faces-config.xml syntax
• In package-explorer, under WebContent WEB-INF
• Name of the bean
• Full qualified class name
• Scope of the bean
• Optional, initialize properties

25. Use the managed beans
• Do the calculation in the class
• Use Expression Language to access properties
• Minimize use of SSJS
• Some examples

26. Java tips for XPages

27. Utility class
• All kind of methods
• Always available as static class
• I added some methods who were translated
from SSJS

28. Date checks
• Remember the TimeDifference horror
• Java provide nice Date checks
• Like… Date.before(Date) or Date.after(Date)

29. Extending a class
• Extend a base class
• Use the methods of the base class

30. Extending a class
• Using the class
• In a XPage

31. Unit test
• Write code to test small portions of code, like methods
• Test if the code is doing what was intended
• Write better Java code
• Use Mock Framework, like EasyMock or Mockito, to simulate objects

32. Unit test for XPages
• More and more Java code in XPages development
• Write Unit test for better code
• On OpenNTF Junit test for Xpages project (thanks Christian Guedemann)

33. And Finally
• Finally will always called, even after a catch
• Use it to recycle objects and close stream readers

34. Thank you
@flinden68
http://nl.linkedin.com/in/flinden68
http://www.elstarit.nl
flinden68@elstarit.nl
https://bitbucket.org/flinden68/bccon-java-demo/src

35. Bonus

36. Eventsource

37. Customizable Toolbar