swing application error on BBB

What is your linux script source?

i saved my script in /usr/bin/myscript.sh

#!/bin/bash

java - jar /home/debian/myapp.jar

trying to execute from my myapp.service that saved on /usr/lib/systemd/system and symliked to /etc/systemd/system

Thank you mike, yes both error are for different java GUI app but difference is number of GUI elements, prior higher later lower, now my answer

1. echo $DISPLAY added prior to java program, no result same error, but this time one extra line i saw that is :0.0
2. I do not know which is default shell on BBB, on desktop there is LXTerminal, i am using that
3. NO, i am not running as you said, i just tested as given bellow

      cd /usr/bin # i stored my script here

      ./myscript.sh

  Both app are working here, i am also tested as following

    cd /usr/bin

    bash myscript.sh,

it is also working.

   4. I added as you said no result

Actually my intention is to start my app automatically after BBB boot for that i did following

i created my myapp.service that saved on /usr/lib/systemd/system and symliked to /etc/systemd/system     H

Hi Mike, on your reply to clem57, you said export DISPLAY=value, here value=?

value would be :0.0 or localhost:0.0 based on what you typed above

so

export DISPLAY=localhost:0.0

Mike

Raman Arumugam wrote:

 

 

Actually my intention is to start my app automatically after BBB boot for that i did following

 

That might be a problem for the reasons clem57 stated, you need to have the xserver started prior to running your program.

Raman Arumugam wrote:

 

1. NO, i am not running as you said, i just tested as given bellow

      cd /usr/bin # i stored my script here

      ./myscript.sh

  Both app are working here, i am also tested as following

    cd /usr/bin

    bash myscript.sh,

it is also working.

 

I'm now confused, is the script working now?

also, try typing

echo $SHELL

to see if it tells you which shell you are running

or if that doesn't produce anything

grep <your username> /etc/passwd

I think you had indicated you are using user debian, so

grep debian /etc/passwd

the last entry will tell you your default shell

Mike

Hi Mike after changing as you said export DISPLAY=localhost:0.0, i got following error message, QMServer.service is my service to auto start my java app through QMServer.sh

debian@beaglebone:/usr/bin$ sudo systemctl daemon-reload

debian@beaglebone:/usr/bin$ sudo systemctl start QMServer.service

debian@beaglebone:/usr/bin$ systemctl status QMServer.service

QMServer.service - QMServer

      Loaded: loaded (/lib/systemd/system/QMServer.service; enabled)

      Active: failed (Result: exit-code) since Thu, 18 Feb 2016 20:11:56 +0530; 11s ago

     Process: 1936 ExecStart=/usr/bin/QMServer.sh (code=exited, status=1/FAILURE)

      CGroup: name=systemd:/system/QMServer.service

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at java.awt.GraphicsEnvironment.createGE(GraphicsEnvironment.java:103)

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEn...a:82)

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at sun.awt.X11.XToolkit.<clinit>(XToolkit.java:126)

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at java.lang.Class.forName0(Native Method)

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at java.lang.Class.forName(Class.java:264)

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at java.awt.Toolkit$2.run(Toolkit.java:860)

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at java.awt.Toolkit$2.run(Toolkit.java:855)

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at java.security.AccessController.doPrivileged(Native Method)

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at java.awt.Toolkit.getDefaultToolkit(Toolkit.java:854)

Feb 18 20:11:56 beaglebone QMServer.sh[1936]: at sun.swing.SwingUtilities2.getSystemMnemonicKeyMask(SwingUtilities2....2020)

debian@beaglebone:/usr/bin$

For command grep debian /etc/passwd, i got following message

debian:x:1000:1000:Demo User:/home/debian:bin/bash

Yeah, I don't think that is going to work, you are going to have an issue if you are trying to start this as a service that's running as a different user than the user who "owns" the display.

That's an X11 security thing. It has been a long time since I have dealt with those kinds of issues, so without having the exact environment in front of me and being able to debug it, I'm not sure I can help much more.

two things to test though

temporarily, before starting the service type xhost +, at the command line, this can pose a security risk, but it will open your display to any user until you exit X, or type xhost -

second, export the DISPLAY variable in your script

meaning at the top of your script add

export DISPLAY=localhost:0.0

you can try that

Mike

That means by default you are running the bash shell, that's good, I just wanted to verify

No luck mike, on your reply you said you are going to have an issue if you are trying to start this as a service that's running as a different user than the user who "owns" the display.

I don't like or want to try start service that's running as a different user than the user who "owns" the display, please let know the way to auto start my service who own display, please share me step to start my service properly without X-server issue.

The one who owns the display is the user that is logged in. You are starting a service as one of the system users, I'm not sure which one, because I don't have access to your system. X11 will prevent users from displaying things on your desktop unless you give them permission. Nothing is going to display unless the x server is started prior to the execution of the program.

There are ways to change the ownership of a process after it starts, at least there is from c, i'm not sure about java.

This is a problem that has been solved before, hopefully I've given you enough info to formulate google queries that will help you achieve the final steps.

Look into the commands I had you type

xhost

export DISPLAY

since your program runs from the command line it seems pretty clear to me that the issue is going to be one of a few things

either the program has no permission to access the DISPLAY

the program or the environment doesn't know which DISPLAY to acess

or it's a timing issue from when the application starts and the xserver is started

Mike

The one who owns the display is the user that is logged in. You are starting a service as one of the system users, I'm not sure which one, because I don't have access to your system. X11 will prevent users from displaying things on your desktop unless you give them permission. Nothing is going to display unless the x server is started prior to the execution of the program.

There are ways to change the ownership of a process after it starts, at least there is from c, i'm not sure about java.

This is a problem that has been solved before, hopefully I've given you enough info to formulate google queries that will help you achieve the final steps.

Look into the commands I had you type

xhost

export DISPLAY

since your program runs from the command line it seems pretty clear to me that the issue is going to be one of a few things

either the program has no permission to access the DISPLAY

the program or the environment doesn't know which DISPLAY to acess

or it's a timing issue from when the application starts and the xserver is started

Mike

ramanc51

If this is a command running on a specific user, see Linux Run Command As Another User or Run as Root User. I think you can start your command when you login, read the part of this How To Launch GUI App With Upstart Script - Ask Ubuntu rather than as the init process.

Clem

Thank you Clem, issue is solved by the first link reference, this issue is solved by adding following lines in my  myscript.sh

export DISPLAY=:0.0

cd /home/debian    // my myapp.jar is  here

su - debian  -c ´java -jar myapp.jar´

Thank you Mike, your guldens was useful to know actual error that i am facing, as you said export DISPLAY is must to run my app.jar without x11 error, finally i found the user own the display by Clem reference then issue is resolved.

Great news! Please share your project here when you get the chance!

Clem

sure, but on later i share my project, i need on more guide i want to load my usb-serial converter with specified name that given below, i created my 81-usb-serial.rules in /etc/udev/rules.d, but this rules is not loaded, it always load ttyUSB0/1 or ttyUSB1/0

SUBSYSTEM=="tty", ATTRS{idVendor}=="1a86", ATTRS{idProduct}=="7523", ATTRS{serial}=="DJJHDH", SYMLINK+="USB-RS232"

SUBSYSTEM=="tty", ATTRS{idVendor}=="0403", ATTRS{idProduct}=="6001", ATTRS{serial}=="A6008isP", SYMLINK+="USB-RS422"

Raman Arumugam wrote:

 

su - debian  -c ´java -jar myapp.jar´

Duh. Of course, I can't believe I did't think of that . I guess I was too focused on the X issues. Glad you got it sorted out.

Mike

OMG! ramanc51

     Please do not change because this area is related to driver code that which expects names to be in a known form. Linux is a beast allowing tons of things to change, Even though it can, you must be a developer knowing what source does to change it.

Clem

clem57 , It seems like adding the symlink attribute should be OK.

Refer to this guide and search for symlink

Writing udev rules

"

KERNEL=="hdc", SYMLINK+="cdrom cdrom0"

The above rule is probably more typical of the types of rules you might be writing. It creates two symbolic links at /dev/cdrom and /dev/cdrom0, both of which point at /dev/hdc. Again, no NAME assignment was specified, so the default kernel name (hdc) is used."

Mike

ramanc51 Since this is a different issue, it should probably be moved into a new thread. That helps people find it in the future.

Mike

OK, i posted on separate thread as udev rules error on BBB with more details