/usr/share/doc/libmina-java-doc/api/org/apache/mina/handler/chain/ is in libmina-java-doc 1.1.7.dfsg-11.
This file is owned by root:root, with mode 0o755.
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/usr/share/doc/libmina-java-doc/api/org/apache/mina/handler/chain/ChainedIoHandler.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/handler/chain/IoHandlerChain.Entry.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/handler/chain/IoHandlerChain.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/handler/chain/IoHandlerCommand.NextCommand.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/handler/chain/IoHandlerCommand.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/handler/chain/package-frame.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/handler/chain/package-summary.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/handler/chain/package-tree.html