Min. ports needed for headless AWT/Swing

[Ronald Klop]

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?

Regards,
Ronald.