/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/ is in libmina-java-doc 1.1.7.dfsg-10.
This file is owned by root:root, with mode 0o755.
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/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/DatagramAcceptor.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/DatagramAcceptorConfig.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/DatagramConnector.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/DatagramConnectorConfig.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/DatagramServiceConfig.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/DatagramSessionConfig.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/SocketAcceptor.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/SocketAcceptorConfig.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/SocketConnector.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/SocketConnectorConfig.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/SocketSessionConfig.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/SocketSessionConfigImpl.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/package-frame.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/package-summary.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/package-tree.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/support/
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/support/DatagramAcceptorDelegate.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/support/DatagramConnectorDelegate.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/support/DatagramSessionConfigImpl.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/support/package-frame.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/support/package-summary.html
/usr/share/doc/libmina-java-doc/api/org/apache/mina/transport/socket/nio/support/package-tree.html