/usr/share/doc/libjava-xmlbuilder-java/api/net/ is in libjava-xmlbuilder-java-doc 0.4-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/Base64.InputStream.html
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/Base64.OutputStream.html
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/Base64.html
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/class-use/
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/class-use/Base64.InputStream.html
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/class-use/Base64.OutputStream.html
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/class-use/Base64.html
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/package-frame.html
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/package-summary.html
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/package-tree.html
/usr/share/doc/libjava-xmlbuilder-java/api/net/iharder/base64/package-use.html