/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/ is in libgnumail-java-doc 1.1.2-7.
This file is owned by root:root, with mode 0o755.
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/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/ListFolderListener.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/NNTPFolder.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/NNTPMessage.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/NNTPRootFolder.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/NNTPStore.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/NNTPTransport.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/class-use/
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/class-use/ListFolderListener.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/class-use/NNTPFolder.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/class-use/NNTPMessage.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/class-use/NNTPRootFolder.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/class-use/NNTPStore.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/class-use/NNTPTransport.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/package-frame.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/package-summary.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/package-tree.html
/usr/share/doc/libgnumail-java/api/gnu/mail/providers/nntp/package-use.html