I am trying to install a Java application on my Linux machine (Slackware).
I have received the following error, and I do not understand it.
Could you advise me how to approach the problem? Thank you.
Here is what I get: (I see that some X11 DISPLAY variable needs to be set, but what value should I give it and how?)
~$ java -jar gate-5.0-beta1-build3048-installer.jar
- ERROR -
java.awt.HeadlessException:
No X11 DISPLAY variable was set, but this program performed an operation which requires it.
java.awt.HeadlessException:
No X11 DISPLAY variable was set, but this program performed an operation which requires it.
at java.awt.GraphicsEnvironment.checkHeadless(Graphic sEnvironment.java:159)
at java.awt.Window.<init>(Window.java:407)
at java.awt.Frame.<init>(Frame.java:402)
at net.sourceforge.mlf.metouia.borders.MetouiaDotsBuf fer.<init>(MetouiaDotsBuffer.java:105)
at net.sourceforge.mlf.metouia.borders.MetouiaDots.<i nit>(MetouiaDots.java:66)
at net.sourceforge.mlf.metouia.borders.MetouiaToolBar Border.<init>(MetouiaToolBarBorder.java:49)
at net.sourceforge.mlf.metouia.MetouiaLookAndFeel.ini tComponentDefaults(MetouiaLookAndFeel.java:241)
at javax.swing.plaf.basic.BasicLookAndFeel.getDefault s(BasicLookAndFeel.java:130)
at javax.swing.plaf.metal.MetalLookAndFeel.getDefault s(MetalLookAndFeel.java:1591)
at javax.swing.UIManager.setLookAndFeel(UIManager.jav a:537)
at javax.swing.UIManager.setLookAndFeel(UIManager.jav a:581)
at com.izforge.izpack.installer.GUIInstaller.loadLook AndFeel(GUIInstaller.java:373)
at com.izforge.izpack.installer.GUIInstaller.<init>(G UIInstaller.java:116)
at sun.reflect.NativeConstructorAccessorImpl.newInsta nce0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInsta nce(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newI nstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Construc tor.java:513)
at java.lang.Class.newInstance0(Class.java:355)
at java.lang.Class.newInstance(Class.java:30
at com.izforge.izpack.installer.Installer.main(Instal ler.java:62)
If you're on the main display, then
export DISPLAY=:0.0
or if you're using csh or tcsh
setenv DISPLAY :0.0
before running your app.
Actually, I'm surprised it isn't set automatically. Are you trying to start this application from a non-graphic terminal? If not, have you modified the default .profile, .login, .bashrc or .cshrc?
Note that setting the DISPLAY to :0.0 pre-supposes that you're sitting at the main display, as I said, or at least that the main display is logged on to your user id. If it's not logged on, or it's a different userid, this will fail.
If you're coming in from another machine, and you're at the main display of that machine and it's running X, then you can use "ssh -X hostname" to connect to that host, and ssh will forward the X display back. ssh will also make sure that the DISPLAY environment variable is set correctly (providing it isn't being messed with in the various dot files I mentioned above). In a "ssh -X" session, the DISPLAY environment variable will have a value like "localhost:11.0", which will point to the socket that ssh is tunnelling to your local box.
you must enable X11 forwarding in you PuTTy
to do so open PuTTy, go to Connection => SSH => Tunnels and check mark the Enable X11 forwarding
Also sudo to server and export the below variable here IP is your local machine's IP
export DISPLAY=10.75.75.75:0.0
Are you running this from within an X11 environment? You can use a terminal window, but it has to be within X (either after a graphical login, or by running startx).
If you're already within a graphical environment, try export DISPLAY=:0 for bash like shells (bash, sh, etc) or setenv DISPLAY :0 for C shell based shells (csh, tcsh, etc)
If you've connected from another machine via SSH, you use the -X option to display the graphical interface on the machine you're sitting at (provided there's an X server running there (such as xming for windows, and your standard Linux X server).
There are many ways to do this. I did something below convenient to me and always works fine.
On your remote server, make sure to install xorg-x11-xauth, xorg-x11-font-utils, xorg-x11-fonts.
Run the Xming Server on you local desktop
On putty, before ssh to the server, enable the X11 forwarding and set the display location to localhost:0.0
On the server, .Xauthority file is generated and notice that the DISPLAY variable is already set.
$ xauth list
$ xauth add
To test it, type xclock or xeyes
Note: To switch user, copy the .Xauthority file to the home directory of the respective user and also export the DISPLAY variable from that user.
One more thing that might be the problem in a case similar to described - X is not forwarded and $DISPLAY is not set when 'xauth' program is not installed on the remote side. You can see it searches for it when you run "ssh -Xv ip_address", and, if not found, fails, which's not seen unless you turn on verbose mode (a fail IMO). You can usually find 'xauth' in a package with the same name.
Very Easy, Had this same problem then what i did was to download and install an app that would help in displaying then fixed the error.
Download this app xming:
http://sourceforge.net/project/downloading.php?
Install, then use settings on this link:
http://www.geo.mtu.edu/geoschem/docs/putty_install.html or follow this steps:
Installing/Configuring PuTTy and Xming
Once PuTTy and Xming have been downloaded to the PC, install according to their respective instructions.
Configuring Xming
Once Xming is installed, run the application called 'XLaunch' and verify that the settings are as shown:
select Default entries on Display Settings windows, click next
click next on Session Type window.
click next on Additional parameters window(Notice clipboard checkbox is true)
save configuration and click to finish.
Configuring PuTTy
After installing PuTTy, double-click on the PuTTy icon on the desktop and configure as shown:
This shows creating a login profile then saving it.
On ssh -> X11, click on checkbox to enable X11 forwarding.
on X display location textbox, type localhost:0.0
save profile then connect remotely to server to test.
Cheers!!!
For those who are trying to get an X Window application working from Windows from Linux:
What worked for me was to setup xming server on my windows machine, set X11 forwarding option in putty when I connect to the linux host and put in my windows ip address with the display port and then the display variable with my windows IP address:0.0
Dont forget to add the linux hosts IP address to the X0.hosts file to ensure that the xming server accepts traffic from that host. Took me a while to figure that out.
I have had the same issue in Ubuntu 14.04.01 when I tried to install JDK 8 and Netbeans if I launch the script inside a Byobu terminal (maybe with Screens happens the same).
Just exit Byobu and (in a graphical terminal) run the script.
Initial Check.
1) When you are exporting the DISPLAY to other machine, ensure you entered the command xhost + on that machine. This command allows to other machine to export their DISPLAY on this machine. There may be security constraints, just know about it. Need to check ssh -X MachineIP will not require xhost + ?
2) Some times JCONSOLE won't show all its process, since those JVM process may run with different user and you are exporting the DISPLAY with another user. so better follow CD_DIR>sudo ./jconsole
3) In WAS (WEBSPHERE); jconsole won't be able to connect its java server process, that time just go till the link, then try connecting it. This worked for me. May be this page is initializing some variables to enable jconsole to connect with that server.
WAS console > Application servers > server1 > Process definition > Java Virtual Machine
I have faced the same issue with AIX (where command line interface only available, There is no DISPLAY UI) machine. I resolved by installing
NX Client for Windows
Step 1: Through that Windows machine, I connected with unix box where GUI console is available.
Step 2: SSH to the AIX box from that UNIX box.
Step 3: set DISPLAY like "export DISPLAY=UNIXMACHINE:NXClientPORTConnectedMentionedOnTitle"
Step 4: Now if we launch any programs which requires DISPLAY; it will be launched on this UNIX box.
VNC
If you installed VNC on UNIX box where display is available; then Windows and NX Client is not required.
Step 1: Use VNC to connect with Unix box where GUI console is available.
Step 2: SSH to the AIX box from that UNIX box.
Step 3: set DISPLAY like "export DISPLAY=UNIXMACHINE:VNCPORT"
Step 4: Now if we launch any programs which requires DISPLAY; it will be launched on this UNIX box.
ELSE
Step 1: SSH to the AIX box from that UNIX box.
Step 2: set DISPLAY like "export DISPLAY=UNIXMACHINE:VNCPORT"
Step 3: Now if we launch any programs which requires DISPLAY; it will be launched on this UNIX box.
Set the display mode is fine and also make sure that the apache Jmeter start from your USER mode, DON'T run in ROOT user.
$ cd /home/USER/apache-jmeter-5.5/
$ ./jmeter
There are two possibilities for it if your app has GUI or not:
1-) If your java app has GUI, firstly ensure that you have installed jdk package normally (non-headless). For example if you installed this:
sudo apt install openjdk-19-jre-headless
remove it:
sudo apt remove openjdk-19-jre-headless
then install the normal version:
sudo apt install openjdk-19-jre
Simply headless is using for GUIless apps. Further information you can look here: Difference between openjdk-6-jre, openjdk-6-jre-headless, openjdk-6-jre-lib
Then, either try to set DISPLAY variable as:
export DISPLAY=:0
or if it does not work (then, probably you have multiple monitors), set as:
export DISPLAY=:1
then run your jar file:
java -jar gate-5.0-beta1-build3048-installer.jar
2-) If your java app has no GUI, while you are running the app, you can try java.awt.headless=true flag as:
java -Djava.awt.headless=true -jar gate-5.0-beta1-build3048-installer.jar
Don't forget to execute "host +" on your "home" display machine, and when you ssh to the machine you're doing "ssh -x hostname"
When I ssh into a server, I can see that the PATH variable is set as required with some custom folders added required.
When I try to connect to the same server using com.jcraft.jsch.JSch library in Java, the PATH is set to something else.
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games
This seems like a out of the box value and doesn't include the custom folders as required. None of the commands that I need to work when I connect through Java unless I give the full path to the executable. I need to connect to different servers and they might be set up with executables in different locations so this is not an option.
I was hoping someone could help me figure out why the ./bashrc file doesn't run when I connect using Java. Should I have to run it manually?
Thanks in advance.
When you connect using command-line SSH, your "default command" is whatever shell you have set up for your username on the remote machine (probably bash, which you can change with chsh), and then bash imports your .bashrc file.
When you connect using JSch, the type of Channel that you open will determine what will be done with your connection. From what I understand about how JSch works, chances are that JSch is not opening bash when it opens the SSH session.
As a general rule of thumb, try using ~/.ssh/environment to set up your PATH instead of .bashrc if the SSH daemon is configured to allow it. This will always be imported before SSH runs any commands, including the shell, so it's more reliable for setting up your PATH.
More info can be found in this Unix StackExchange post about .bashrc, PATH, and SSH, including some alternatives to my answer.
I was wondering if it was possible to execute commands from PHP to a Java prompt which is already running?
I have tried the solution listed here:
How to run a shell command through PHP code?
and this provided no functionality
Let me explain
The java is running on one screen of the linux server
sudo apt-get install screen
and running the .jar file through the command line.
I am then running a webserver, which will have an admin accessibility to restricted areas, which will contain scrips to run specific commands through that already running .jar file?
You can implement some kind of IPC. The java file listens to a port and receives the commands. Or you can write the commands in a specific file which the java programm reads. I think under linux you can also use shared memory: http://www.php.net/manual/en/book.shmop.php
It is possible by sending the command to the screen session. I used this for a minecraft server once.
screen -S <sessionname> -X stuff "<command>\r"
This would (IIRC) provide the same output as if you where inside the screen, typed the command and pressed enter.
I hope this was what you wanted.
I have created a Java GUI application that is running in Windows. Now I want it to run it on a headless Linux instance that does not support GUI. I wanted to convert the GUI to TUI. Is there a way I can substitute some classes and make it run in Linux by TUI. Please help.
You can use PeterMmm's suggestion http://www.pitman.co.za/projects/charva/index.html
Or, you can run the GUI on your local machine by running an X server, then connecting to the Linux box using ssh -X. That will show the GUI on your local machine, but the program is actually running on the linux box.
Or, you can run XVFB to fake a GUI on the Linux box. You won't be able to see the GUI or interact with it in any way, but that might not matter to you.
For the sake of spreading a simple and effective solution, I copy the answer provided by #fossfreedom on SA "Ask Ubuntu":
sudo apt-get install xvfb
then:
xvfb :1 -screen 0 800x600x8 &
export DISPLAY=":1"
java application_name.jar
or
xvfb-run -a -e /tmp/some/log/file.log java -jar /home/user/somejava.jar
-> see: https://askubuntu.com/questions/50599/how-do-you-run-a-gui-application-without-gui-gui-application-as-daemon-on-headl
There are some ncurses implementations for Java available like this one: http://www.pitman.co.za/projects/charva/index.html
If you are connecting from another X running Linux machine put following to your user ssh config (~/.ssh/config):
Compression yes
CompressionLevel 9
ForwardX11 yes
ForwardX11Trusted yes
Then when you login to remote Linux machine your GUI going to be forwarded to local screen. Note that it could be slow... notably some AWT applications are really slow even on LAN.
If on Windows, intall CygWin and its Xserver components. Also OpenSSH can be helpful. When you going to connect through CygWin's ssh, use the same config as above. Of course run Xserver prior connecting to remote machine. You also can use Putty to connect to remote, but don't forget to enable X11 forwarding and compression in session config.
Remote machine must have xauth installed + sshd must have X11Forwarding enabled. If OK echo $DISPLAY will show localhost:10.
I have a java GUI jar file that i need to launch at my unix terminal. My system admin says "X is already enabled via ssh". But when i type xterm it says
xterm Xt error: Can't open display: xterm: DISPLAY is not set
I did some reading and it says i have to login using
$ssh -X mylogin#xyz
So my question is:
1) What should i do next...i typed xterm again but the window does not launch
2) Suppose i get it working somehow. How can i launch my java GUI. (do i simply type the jar file name)?
Thank you all for your help.
I am assuming you are connecting from your own computer to some server running SSH. First off, you need to install an X11 server on your own machine if you don't have one already. The terminology here is confusing - if you're connecting to another machine by SSH, you're probably used to thinking of your own machine as the client and the remote one as the server. But in the case of X11, those roles are reversed.
Then, you'll need to start X11 on your own machine and within that, launch an xterm. Then from that xterm, you can run ssh -X myserver.example.com and once logged into that remote server, run java -jar myapplication.jar and it ought to work.
The specific mechanism for launching an X Server on your own machine varies by operating system. On Linux/FreeBSD/etc, you're probably running one already. On a Mac, X11 is available under Applications if you've installed the developer tools. On Windows you'll need something like Xming
Go to your unix terminal and do:
export DISPLAY=<ip_addr>:0
For e.g. I would do export DISPLAY=10.18.192.89:0.
The ip-address is of the machine where you want to see the GUI and that machine should have an Xterm client running.