Develop Reference

Working with MCRTsim simulator on a LINUX system

I am trying to use the MCRTsim simulator in my research work. As documented in https://resl.csie.nptu.edu.tw/dokuwiki/doku.php?id=guide, I run this command java -jar MCRTsim/dist/MCRTsim2.8.jar in specified directory, but the simulation window did not pop up. Instead, I got following exceptions:
Exception in thread "main" java.lang.NullPointerException
at java.base/java.io.Reader.<init>(Reader.java:167)
at java.base/java.io.InputStreamReader.<init>(InputStreamReader.java:109)
at org.apache.commons.io.IOUtils.copy(IOUtils.java:2440)
at org.apache.commons.io.IOUtils.toString(IOUtils.java:1084)
at org.apache.commons.io.IOUtils.toString(IOUtils.java:1110)
at userInterface.frontEnd.SimulationViewer.setComboBox(SimulationViewer.java:529)
at userInterface.frontEnd.SimulationViewer.initialize(SimulationViewer.java:359)
at userInterface.frontEnd.SimulationViewer.<init>(SimulationViewer.java:97)
at userInterface.UserInterface.initialize(UserInterface.java:45)
at userInterface.UserInterface.<init>(UserInterface.java:31)
at mcrtsim.MCRTsim.main(MCRTsim.java:55)
I am using Ubuntu system and JDK 11. I have not used Java much. I am not able to understand what this error is saying. Would anyone please help me with this?

Finally, I got the solution to this problem. I think this simulator is compatible with openjdk-8. So, I removed openjdk-11 from my system and installed openjdk-8.
After installing openjdk-8, I run the command java -jar dist/MCRTsim2.8.jar . This time I got the following error:
Exception in thread "main" java.awt.AWTError: Assistive Technology not
found: org.GNOME.Accessibility.AtkWrapper
at java.awt.Toolkit.loadAssistiveTechnologies(Toolkit.java:807)
at java.awt.Toolkit.getDefaultToolkit(Toolkit.java:886)
at java.awt.Window.getToolkit(Window.java:1358)
at java.awt.Window.init(Window.java:506)
at java.awt.Window.<init>(Window.java:537)
at java.awt.Frame.<init>(Frame.java:420)
at javax.swing.JFrame.<init>(JFrame.java:233)
at userInterface.UserInterface.initialize(UserInterface.java:37)
at userInterface.UserInterface.<init>(UserInterface.java:31)
at mcrtsim.MCRTsim.main(MCRTsim.java:55)
After that, I followed this blog https://askubuntu.com/questions/695560/assistive-technology-not-found-awterror to rectify the above error.
I just commented this line #assistive_technologies=org.GNOME.Accessibility.AtkWrapper in /etc/java-8-openjdk/accessibility.properties file.
And, it started working.

Resolve cd : Cannot find path "pathname" because it does not exist. (When it does.)

Everytime I run some code that I wrote in java on Visual-Studio-Code ,except from the first time , I get this error in the terminal but it does not affect the program's execution . What is the issue here? I've tried to access the files with cmd and I did it successfuly .
Here is the error that I get: https://prnt.sc/wmxor3
Thanks in advance.

Java Exception when opening iReport

Here is the error I'm getting. Tried to open other version of ireport and didn't encountered any errors.
Exception in thread "main" java.lang.IllegalArgumentException: port out of range:1313821769
at java.net.InetSocketAddress.checkPort(InetSocketAddress.java:143)
at java.net.InetSocketAddress.<init>(InetSocketAddress.java:188)
at java.net.Socket.<init>(Socket.java:244)
at org.netbeans.CLIHandler.initialize(CLIHandler.java:661)
at org.netbeans.CLIHandler.initialize(CLIHandler.java:346)
at org.netbeans.MainImpl.execute(MainImpl.java:195)
at org.netbeans.MainImpl.main(MainImpl.java:76)
at org.netbeans.Main.main(Main.java:75)
I am using java 7 on my ireport.conf, also I am using Ubuntu
jdkhome="/usr/jdk1.7.0_55.for.tmpfs/"
The application is working fine this morning and this just happens,
I've tried search for solutions but the only solutions I found on the internet is to check whether I am using java 7 which I am.
I guess the port has something to do with this but I'm not sure where to start.

Problem is with the lock file.
Try to find it using this command:
find /home/your_user_name -name lock
It will be located in path like /home/your_user_name/.ireport/4.5.1/lock
Delete this file and try to start iReport again.

Selenium HTML Runner Error (Multi-Window)

I'm trying to execute html tests (recorded with Selenium IDE on firefox) with the following command :
$> java -jar /path/to/selenium-html-runner-3.0.0.jar -htmlSuite "*firefox" "http://www.google.com" "/path/to/test.html" "/path/to/results.html"
I'm getting the following error :
$> Multi-window mode is longer used as an option and will be ignored.
Exception in thread "main" java.lang.NullPointerException
at org.openqa.selenium.server.htmlrunner.HTMLLauncher.validateArgs(HTMLLauncher.java:261)
at org.openqa.selenium.server.htmlrunner.HTMLLauncher.mainInt(HTMLLauncher.java:218)
at org.openqa.selenium.server.htmlrunner.HTMLLauncher.main(HTMLLauncher.java:273)
Any ideas of want is wrong here ?
Thanks !

This seems to be a bug that was fixed in the recently released 3.0.1.

Unable to load library 'cxcore': libcxcore.so: cannot open shared object file: No such file or directory

When I run project jar file, it gives following error message
Exception in cameracheck Thread - check();java.util.concurrent.ExecutionException: java.lang.UnsatisfiedLinkError: Unable to load library 'cxcore': libcxcore.so: cannot open shared object file: No such file or directory
Exception in thread "main" java.lang.NullPointerException
at CameraProperties.CheckForCameraPlugin.check(CheckForCameraPlugin.java:55)
at Main.Main.main(Main.java:49)
Thanks Haris. You spend much time with me. Thanks a lot. The issue has
been sorted out. I provided 2 commands inside /usr/local/lib. 1) sudo
ln -s libopencv_core.so.2.4.6 libcxcore.so 2) sudo ln -s
libopencv_highgui.so.2.4.6 libhighgui.so. In another computer with
2.3.1 version of opencv, I provided the same commands with corresponding version number under /usr/lib. Thanks again. I am so
happy. :) :) :)