How to get notification if Boolean variable has been changed?

How to get notification if Boolean variable has been changed?

References

Reference NO 1

http://stackoverflow.com/questions/15188327/how-to-get-notification-if-boolean-variable-has-been-changed

Reference NO 2

http://stackoverflow.com/questions/7763050/how-do-i-pass-a-boolean-value-between-classes

Reference NO 3

http://dev.vaadin.com/svn/versions/6.1/src/com/vaadin/ui/Button.java

Reference NO 4

http://pmd.sourceforge.net/pmd-4.3/rules/design.html

Reference NO 5

http://docs.puppetlabs.com/puppet/2.7/reference/lang_datatypes.html

Reference NO 6

https://forums.oracle.com/thread/2043655?start=0&tstart=0

Reference NO 7

http://help.eclipse.org/helios/topic/org.eclipse.platform.doc.isv/reference/api/org/eclipse/core/resources/IPathVariableManager.html

Reference NO 8

http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/Boolean.html