Use notes objects in memory and other useful java tips for xpages development

07-04-2023 @EngageUG #engageug 1

Use Notes objects in memory and other useful Java tips for XPages development

Frank van der Linden


@flinden68

http://flinden68.wordpress.com

http://nl.linkedin.com/in/flinden68

[email protected]


mailto:[email protected]


DisclaimerAll 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.Please visit the session of Paul Withers and Martin Jinoch.Or even better use OpenNTF essentials

http://openntf.org/main.nsf/project.xsp?r=project/OpenNTF%20Domino%20API

http://openntf.org/main.nsf/project.xsp?r=project/OpenNTF%20Essentials


Roadmap• Notes objects in memory• Use of JSON• Managed beans• Java tip for XPages

• Date checks• Utility class• Extending classes• Use of finally


Notes objects in memory


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


What is Serialization


XPages Java doc to the rescue


Put Notes document in memory• Get Notesdocument

• Wrap Notesdocument into a DominoDocument


Access fields• First check if document isRecycled

• Access field


On a XPage and more• In a computed field

• In an edit box

• Update the backend document


Demo


What about attachments• Get easy access to your attachements


What about attachments• No calculation of paths• Works both in XPinc and Web

• Call the attachment URL


Demo


Use buildin JSON classes


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


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


Managed beans


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


Faces-config.xml syntax• Name of the bean• Full qualified class name• Scope of the bean• Optional, initialize properties


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


Java tips for XPages


Utility class• All kind of methods• Always available as static class• I added some methods who were

translated from SSJS


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


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


Extending a class• Using the class

• In a XPage


Questions


Credits• DominoDocument, thanks Jesse Gallaghar for pointing me in the right direction.• Utility Class, the base taken from the Help Application from OpenNTF• Presentation, reveal.js• Demo database runs on Domino 9.0.1• Demo database needs the Extension Library from OpenNTF• XPages Java doc, http://

public.dhe.ibm.com/software/dw/lotus/Domino-Designer/JavaDocs/XPagesExtAPI/8.5.2/index.html?overview-summary.html

http://www.openntf.org/Projects/pmt.nsf/041f04f1ecaf8e95862570e2007ed36b/426cb81230b6f94a8625789000830762!OpenDocument

http://lab.hakim.se/reveal-js/#/

http://www.openntf.org/main.nsf/project.xsp?r=project/XPages%20Extension%20Library

http://public.dhe.ibm.com/software/dw/lotus/Domino-Designer/JavaDocs/XPagesExtAPI/8.5.2/index.html?overview-summary.html




@flinden68

http://flinden68.wordpress.com


[email protected]

Thank you


mailto:[email protected]


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