https://docs.oracle.com/javase/jp/11/docs/api/java.desktop/javax/swing/text/html/StyleSheet.BoxPainter.html
StyleSheet.BoxPainter (Java SE 11 & JDK 11 )
java sestylesheetjdk
https://docs.oracle.com/en/java/javase/21/docs/api/java.desktop/javax/swing/text/html/StyleSheet.BoxPainter.html
StyleSheet.BoxPainter (Java SE 21 & JDK 21)
declaration: module: java.desktop, package: javax.swing.text.html, class: StyleSheet, class: BoxPainter
java sestylesheetjdk