https://docs.oracle.com/javase/jp/10/docs/api/org/xml/sax/DocumentHandler.html
DocumentHandler (Java SE 10 & JDK 10 )
java sejdk
https://lxr.kde.org/source/office/klevernotes/src/logic/documentHandler.h?v=kf5-qt5
/kf5-qt5/office/klevernotes/src/logic/documentHandler.h
KDE Source Cross Reference
officesrclogich