Min. ports needed for headless AWT/Swing

Aryeh Friedman aryeh.friedman at gmail.com
Wed Jul 1 14:27:12 UTC 2020 

On Wed, Jul 1, 2020 at 10:03 AM <matthew at freebsd.org> wrote:

> On 01/07/2020 13:56, Aryeh Friedman wrote:
> > On Wed, Jul 1, 2020 at 8:54 AM Ronald Klop <ronald-lists at klop.ws> wrote:
> >
> >>
> >>
> >> *Van:* Aryeh Friedman <aryeh.friedman at gmail.com>
> >> *Datum:* woensdag, 1 juli 2020 14:36
> >> *Aan:* Ronald Klop <ronald-lists at klop.ws>
> >> *CC:* freebsd-java at freebsd.org, Michael Osipov <1983-01-06 at gmx.net>
> >> *Onderwerp:* Re: Min. ports needed for headless AWT/Swing
> >>
> >>
> >>
> >> On Wed, Jul 1, 2020 at 8:30 AM Ronald Klop <ronald-lists at klop.ws>
> wrote:
> >>
> >>>
> >>> Van: Aryeh Friedman <aryeh.friedman at gmail.com>
> >>> Datum: woensdag, 1 juli 2020 14:03
> >>> Aan: Ronald Klop <ronald-lists at klop.ws>
> >>> CC: freebsd-java at freebsd.org, Michael Osipov <1983-01-06 at gmx.net>
> >>> Onderwerp: Re: Min. ports needed for headless AWT/Swing
> >>>>
> >>>>
> >>>>
> >>>> On Wed, Jul 1, 2020 at 7:58 AM Ronald Klop <ronald-lists at klop.ws>
> >>> wrote:
> >>>>>
> >>>>>
> >>>>> Van: Aryeh Friedman <aryeh.friedman at gmail.com>
> >>>>> Datum: woensdag, 1 juli 2020 13:33
> >>>>> Aan: Ronald Klop <ronald-lists at klop.ws>
> >>>>> CC: freebsd-java at freebsd.org, Michael Osipov <1983-01-06 at gmx.net>
> >>>>> Onderwerp: Re: Min. ports needed for headless AWT/Swing
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> On Wed, Jul 1, 2020 at 5:52 AM Ronald Klop <ronald-lists at klop.ws>
> >>> wrote:
> >>>>>>>
> >>>>>>> Van: Aryeh Friedman <aryeh.friedman at gmail.com>
> >>>>>>> Datum: maandag, 29 juni 2020 20:59
> >>>>>>> Aan: Michael Osipov <1983-01-06 at gmx.net>
> >>>>>>> CC: freebsd-java at freebsd.org
> >>>>>>> Onderwerp: Re: Min. ports needed for headless AWT/Swing
> >>>>>>>>
> >>>>>>>> On Mon, Jun 29, 2020 at 2:28 PM Michael Osipov <
> 1983-01-06 at gmx.net>
> >>> wrote:
> >>>>>>>>
> >>>>>>>>> Am 2020-06-29 um 17:43 schrieb Aryeh Friedman:
> >>>>>>>>>> I have a java application that works fine with setenv DISPLAY
> >>> :0.0 on my
> >>>>>>>>>> desktop FreeBSD 12.1 (amd64) [with Xfce4] but when I attempt to
> >>> run the
> >>>>>>>>>> same app on a VM that has the minimum ports needed to install
> >>> OpenJDK 8
> >>>>>>>>> and
> >>>>>>>>>> Tomcat I get an exception saying that it can't connect to the X
> >>> server
> >>>>>>>>> even
> >>>>>>>>>> though I did setenv DISPLAY desktop:0.0 (and xhost + on the
> >>> desktop).
> >>>>>>>>>> Note it is the same user on both machines (NIS/NFS password
> >>> DB/home dirs)
> >>>>>>>>>> doing the running on both machines but is a different user then
> >>> the one
> >>>>>>>>>> logged in at the console (I do all my development in a separate
> >>> account)
> >>>>>>>>>
> >>>>>>>>> Are you look for "-Djava.awt.headless=true"?
> >>>>>>>>>
> >>>>>>>>
> >>>>>>>> Since this is a screen capture/recording program (which I am the
> >>> developer)
> >>>>>>>> I need to be able to capture the console (running X) that I am
> >>> currently
> >>>>>>>> on.   So the question is what is the minimum set of ports/packages
> >>> I need
> >>>>>>>> to install on the VM to make it see and X server?   It should be
> >>> noted the
> >>>>>>>> program has no GUI but does use java.awt.Robot#createScreenCapture
> >>> (using
> >>>>>>>> the full screen resolution as it's bounds) individual frames of
> the
> >>> longer
> >>>>>>>> video.
> >>>>>>>>
> >>>>>>>> Here is the specific exception I am attempting to fix:
> >>>>>>>> On desktop (192.168.11.20)
> >>>>>>>> % xhost +
> >>>>>>>>
> >>>>>>>> On VM (192.168.11.4):
> >>>>>>>> % setenv DISPLAY 192.168.11.20:0.0
> >>>>>>>> % java
> >>>>>>>>
> >>>
> -javaagent:/usr/local/share/java/classes/jacocoagent.jar=destfile=/usr/home/aryeh/fnwe-scap-1a1.C036/jacoco.exec,jmx=true,excludes=thistest/*:test/*
> >>>>>>>> -cp
> >>>>>>>>
> >>>
> /usr/home/aryeh/fnwe-scap-1a1.C036/scrap/www/WEB-INF/lib/fnwe-scap-1a1.jar:/usr/local/share/java/classes/thisTest.jar:/usr/local/share/java/classes/pcCommon.jar:/usr/local/share/java/classes/pcUtil.jar
> >>>>>>>> test.TestMain
> >>>>>>>>
> >>>>>>>> Result of the jvm invocation on the VM (not it works no problem
> >>> su(do)'ing
> >>>>>>>> to another account on the desktop if I do setenv DISPLAY :0.0):
> >>>>>>>>
> >>>>>>>> Caused by: java.awt.AWTError: Can't connect to X11 window server
> >>> using
> >>>>>>>> '192.168.11.20:0.0' as the value of the DISPLAY variable.
> >>>>>>>> at sun.awt.X11GraphicsEnvironment.initDisplay(Native Method)
> >>>>>>>> at
> >>>
> sun.awt.X11GraphicsEnvironment.access$200(X11GraphicsEnvironment.java:65)
> >>>>>>>> at
> >>> sun.awt.X11GraphicsEnvironment$1.run(X11GraphicsEnvironment.java:115)
> >>>>>>>> at java.security.AccessController.doPrivileged(Native Method)
> >>>>>>>> at
> >>> sun.awt.X11GraphicsEnvironment.<clinit>(X11GraphicsEnvironment.java:74)
> >>>>>>>> at java.lang.Class.forName0(Native Method)
> >>>>>>>> at java.lang.Class.forName(Class.java:264)
> >>>>>>>> at
> >>> java.awt.GraphicsEnvironment.createGE(GraphicsEnvironment.java:103)
> >>>>>>>> at
> >>>>>>>>
> >>>
> java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:82)
> >>>>>>>> at
> test.scap.TestVideoFrame.testCaptureFrame(TestVideoFrame.java:76)
> >>>>>>>>
> >>>>>>>> _______________________________________________
> >>>>>>>>> freebsd-java at freebsd.org mailing list
> >>>>>>>>> https://lists.freebsd.org/mailman/listinfo/freebsd-java
> >>>>>>>>> To unsubscribe, send any mail to "
> >>> freebsd-java-unsubscribe at freebsd.org"
> >>>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> --
> >>>>>>>> Aryeh M. Friedman, Lead Developer, http://www.PetiteCloud.org
> >>>>>>>> _______________________________________________
> >>>>>>>> freebsd-java at freebsd.org mailing list
> >>>>>>>> https://lists.freebsd.org/mailman/listinfo/freebsd-java
> >>>>>>>> To unsubscribe, send any mail to "
> >>> freebsd-java-unsubscribe at freebsd.org"
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>
> >>>>>>> Hi,
> >>>>>>>
> >>>>>>> Can you start any other X application on the VM using the DISPLAY
> >>> setting? Like /usr/ports/x11/xeyes. Than you know if it is something
> with X
> >>> instead of something with Java. I guess it is something with X.
> >>>>>>> I guess your desktop is not listening for external connections to
> >>> the X server or your routing between the VM and the desktop does not
> work.
> >>>>>>> Or start a X server in the VM and use DISPLAY=:0.0 again.
> >>>>>>
> >>>>>>
> >>>>>> Don't have any X components installed except for the ones required
> by
> >>> "make/make install" on openjdk8.   The reason for this post in the
> first
> >>> place was to figure out the minimum set of ports needed to get a
> working
> >>> DISPLAY variable in the first place.
> >>>>>>
> >>>>>>
> >>>>>> --
> >>>>>> Aryeh M. Friedman, Lead Developer, http://www.PetiteCloud.org
> >>>>>
> >>>>> I'm 99% sure you don't need any additional ports to get a working
> >>> DISPLAY variable.
> >>>>>
> >>>>> It will probably help to start your X server with "-listen tcp". But
> I
> >>> don't have enough information to be sure about that and how to
> configure
> >>> that in your setup.
> >>>>
> >>>>
> >>>> I think that might work if in fact there was an X server on the VM:
> >>>>
> >>>> root at dnixon:~ # X -listen-tcp
> >>>> X: Command not found.
> >>>> root at dnixon:~ # ls /usr/local/bin/X*
> >>>> ls: No match.
> >>>> root at dnixon:~ # ls /usr/local/bin/x*
> >>>> /usr/local/bin/x265 /usr/local/bin/xicclu /usr/local/bin/xmlcatalog
> >>> /usr/local/bin/xslt-config
> >>>> /usr/local/bin/xaegis /usr/local/bin/xjc /usr/local/bin/xmlcatmgr
> >>> /usr/local/bin/xsltproc
> >>>> /usr/local/bin/xft-config /usr/local/bin/xkbcomp
> /usr/local/bin/xmllint
> >>> /usr/local/bin/xsubpp
> >>>> /usr/local/bin/xgettext /usr/local/bin/xml2-config
> /usr/local/bin/xmlwf
> >>> /usr/local/bin/xxd
> >>>> root at dnixon:~ # ls /usr/local/sbin/x*
> >>>> ls: No match.
> >>>> root at dnixon:~ # ls /usr/local/sbin/X*
> >>>> ls: No match.
> >>>> root at dnixon:~ # java -version
> >>>> openjdk version "1.8.0_252"
> >>>> OpenJDK Runtime Environment (build 1.8.0_252-b09)
> >>>> OpenJDK 64-Bit Server VM (build 25.252-b09, mixed mode)
> >>>>
> >>>>
> >>>> --
> >>>> Aryeh M. Friedman, Lead Developer, http://www.PetiteCloud.org
> >>>
> >>> In an earlier message you talked about "setenv DISPLAY 192.168.11.20:0
> .0".
> >>> That is the IP address of your desktop. So the X server must be
> running on
> >>> your desktop.
> >>>
> >>> You want the VM to screencapture the screen of the desktop? Or do you
> >>> want the VM to screencapture the screen of the VM?
> >>
> >>
> >> On the desktop... finally got it to capture the screeen on the desktop
> via
> >> what I tried above but now have a second problem with is the audio
> capture
> >> is there anyway to make the following Java snippet work with a remote
> mic
> >> (works fine on the desktop with a local mic on dsp2.0)?
> >>
> >>                  fmt=new AudioFormat(160000,8,2,true,true);
> >>                  mic=AudioSystem.getTargetDataLine(fmt);
> >>                  mic.open(fmt);
> >>                  mic.start();
> >> --
> >> Aryeh M. Friedman, Lead Developer, http://www.PetiteCloud.org
> >>
> >>
> >> Good that it is solved. Would you mind sharing what the solution was?
> >>
> >
> > Adding -- -listen tcp to my call to startx on the desktop (I was confused
> > about which machine was the server and which was the client since the
> > relationship is reverse of the normal order.... i.e. the server is the
> > local machine and the client is the remote one not the other way around
> for
> > X)
> >
> >
>
> Be aware that running remote X applications against a local X server
> will transmit all of the X related traffic across the network in the
> clear -- which is roughly as bad as running old-style rsh(1).
>
> That may or may not be a problem for your use case, but in general look
> into tunnelling your X traffic across an SSH session -- see the
> description of the  `-X` and `-Y` flags in ssh(1).  SSH basically sets
> up a port forwarding from the loopback on the (remote) X client to the
> (local) X server on your desktop, and will set DISPLAY and XAUTHORITY to
> appropriate values for you automatically.  Plus you don't need to enable
> a tcp listener for X, which in itself just offers up a massively
> enlarged attack surface.
>

1. ssh -X and -Y were not working (tried them first).
2. It is only used on a wired LAN (no WiFi at all) on a double NAT'ed (both
private IP spaces on different 10.X.X.X and 192.168.X.X connection both via
physically separate routers [cable modem and a desktop router]) between two
machines on the same switch (the only machines on the switch) in my home
office that only me and my SO use (they are also a Java programmer and
wrote the encryption front end library we use for our stuff so I trust them
completely)
3. There are no applications on the VM that make arbitrary network
connections without direct user approval (i.e. no mail server/client and/or
web browser)

>
>         Cheers,
>
>         Matthew
> _______________________________________________
> freebsd-java at freebsd.org mailing list
> https://lists.freebsd.org/mailman/listinfo/freebsd-java
> To unsubscribe, send any mail to "freebsd-java-unsubscribe at freebsd.org"
>


-- 
Aryeh M. Friedman, Lead Developer, http://www.PetiteCloud.org

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