/usr/share/doc/openjdk-6-jre-headless/examples/nio/ is in openjdk-6-demo 6b31-1.13.3-1ubuntu1.
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/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/AcceptHandler.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/Acceptor.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/B1.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/BN.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/BP.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/ChannelIO.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/ChannelIOSecure.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/Content.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/Dispatcher.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/Dispatcher1.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/DispatcherN.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/FileContent.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/Handler.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/MalformedRequestException.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/N1.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/N2.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/README.txt
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/Reply.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/Request.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/RequestHandler.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/RequestServicer.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/Sendable.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/Server.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/StringContent.java
/usr/share/doc/openjdk-6-jre-headless/examples/nio/server/URLDumper.java