I have 4-5 Instances of JAVA/JVM Running in Windows Server 2008 R2 Server, When I Open up Task Scheduler, I can see java.exe running, I am "not" able to find out the java instance details like what is the program? is it Tomcat? is it some Command Line etc?
From Task Manager , I could not get it? is there a way to find out from Command Line (or) Powershell?
In task manager, click View>Select Columns... and opt the command line column.
Open cmd and type following command, it will show all java processes:
jps -vlm
since you asked the powershell solution, you may use Get-Process java | select Processname, Path
Cheers,
GJ
It's %SystemRoot%\System32. The copy of java.exe is placed there during installation. You can also right click on the process and look up containing folder.
Related
I have a Windows server which run several java .jar running in the background.
For example programABC.jar, programDEF.jar, and so on.
They were triggered trough the Windows task scheduler.
I can see through DOS command line tasklist or Windows "Task Manager" there are a couple of java.exe currently running, I can also tell their Process ID. But I don't know which instance belong to which jar program. How to identify these processes?
As a comparison in linux if we have the Process ID we can just cat /proc/YOURPID/maps that will give a clue what is the program name, run from where, etc.
Thanks in advance
In Task Manager processes tab click View|Select Columns. Scroll down the list then select "Command Line" then OK. You should see the command line of the process which should include the .jar file used.
I'd like to know how it is started. What is the command to start this java process ? What I mean is I have one running java process, and I'd like to know the command to start it, such as what is the main class and what is the arguments, etc.
Any tool for that ? Thanks
There is a command line tool that comes with the JDK: jps, that will give you the list of java processes being run at the moment you execute the command, the arguments given to the method main and the parameters used for the JVM. Try this:
path\to\jdk\bin\jps -m -l -v
It won't give you the exact command used to start the process, but it will give you a hint of how to "rebuild" that command.
For more info, if you are on a decent distro of linux, try man jps or if you are on Windows, see the Oracle documentation about jps.
Your question wasn't clear. If you are looking to find the command that launched this process than you can look at the property sun.java.command. This will give you the main class name and arguments passed to it. java.class.path property gives you the class path. You can get the arguments passed to the java command itself by using ManagementFactory.getRuntimeMXBean().getInputArguments() method. Using all these you should be able to reconstruct the java command.
If you use Windows, you can use the Taskmanager, go to the Process/Details Tab, where you can see the PID for each Process. There you can add a column for the command line (e.g. in German its "Befehlszeile", i'm not sure how that column is labeled in English).
Then just look at the java.exe/javaw.exe Processes.
You could also use the alternative Taskmanager from Microsoft, Process Explorer, afaik there you can just click right on a process and select details.
I would like to monitor a local Java application using JVisualVM. When I'm starting it, the popup 'Local java application cannot be monitored' or 'Local Applications Cannot Be Detected' is shown. I have read here that it is a permissions problem. Every time when I grant full access to folder %TMP%hsperfdata_MY_USER_ID to me (logged user) and everyone (windows user), the permissions are reset when I start JVisualVM.
I know that another solution is to delete hsperfdata_MY_USER_ID, but why does the permissions trick not work? Is the permissions folder reset a Windows feature?
System : Windows 7
Tested on cmd started as administrator. I use the same accounts and I do not pass any JVM parameters such as com.sun.management.jmxremote.port=XXXX.
For people stumbling here who have a FAT-type file system:
Make a directory (e.g. e:\temp) on an NTFS disk.
Start both java and jvisualvm with an environment variable TMP=E:\temp.
There are three options to set the environment variable for java:
In your IDE, go to the project options or launch options and find the 'Environment' entry, then enter TMP=E:\temp
Open a cmd prompt, and execute set TMP=E:\temp before launching youur java application from the same prompt.
Put the two lines you'd enter at the cmd prompt in a .bat file. Optinally add pause at the end of the bat file to prevent the console window from disappearing in case of a runtime exception or vm crash.
Similarly, for JVisualVM, use one of the last two options.
I had the 'Local Applications Cannot Be Monitored' problem, got it solved like this:
Exit all java processes
Delete existing folder %TMP%\hsperfdata_username
Start jvisualvm, which created the folder with a different casing: %TMP%\hsperfdata_USERNAME
My problem and solution have nothing to do with permissions, so may not work for the original problem in the question.
Also see https://visualvm.github.io/troubleshooting.html#jpswin
This answer is a bit trivial but might still save time.
Check your java application is not lauched with the "-XX:-UsePerfData" option.
My username: A4000000
I had to delete C:\Users\A4000000\AppData\Local\Temp\hsperfdata_a4000000
AppData is a hidden folder.
Then once starting VisualVM again, it created the following:
C:\Users\A4000000\AppData\Local\Temp\hsperfdata_A4000000
Notice the case difference.
Then start:
C:\visualvm_213\bin> visualvm.exe --jdkhome "C:\Program Files\Java\jdk1.8.0_202" --userdir "C:\Temp\visualvm_userdir"
I followed the instructions on the Datomic site: http://docs.datomic.com/getting-started.html, but I'm getting this error when trying to start up the datomic shell prompt. I'm using a windows machine. Any suggestions? I tried the same thing on my linux box and did not get this error.
Edit: moved to a different windows machine and it's working. If I have time to troubleshoot this problem and I find a solution I'll report back
I noticed that you cannot run the shell.cmd from within the bin directory, you need to call it with bin\shell.cmd from the parent directory... hope that helps.
In case you are using cygwin/bash and call bin/shell :
The java runtime on windows does not understand classpath with a ":"
but this is what you get from bin/classpath.
Either correct this or use DOS-CMD shell and call bin/shell.cmd inside.
Regards
Some tips for running datomic on Windows (7 at least):
Do not download datomic into Program Files. On startup, it creates logging directories and temp files into its own directories, so unless you run the command prompt as Administrator, you're gonna have screens full of Unable to write to file... errors.
You need to run datomic as such (assuming you extracted the download to C:)
c:\datomic-free-0.x.xxxx>bin\shell.cmd
Note the backslash. Tripped me up forever coming from *nix world.
After that, return to your regularly scheduled datomic tutorials.
I added a value at:
HKLM\Software\Microsoft\Windows\CurrentVersion\Run
That looks like this:
Value Name: LDE
Value Data: "java -jar C:\LDE\lde.jar"
Really with the quotes (Because all the others where also with quotes). After adding this, I restarted my computer, but it didn't start automatically.
Will wrapping my jar in an exe help?
I'm running Windows 7.
Any help?
Thanks in advance.
Update:
When I remove the quotes, it works. But now there is appears also a terminal, which I don't need...
A couple of things to note here, concerning the two different issues in the problem:
Format of Windows Run keys
From the Microsoft Windows XP knowledge base:
Run keys cause programs to
automatically run each time that a
user logs on. The Windows XP registry
includes the following four Run keys:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
Each of these keys has a series of
values. The values allow multiple
entries to exist without overwriting
one another. The data value for a
value is a command line.
Note the emphasis on the last line. The moment quotes are used, the command is bound to fail execution in the same manner it fails as if executed from a command prompt.
Also, note that the above approach is for Windows XP and does hold good for Windows 7. More details can be found in this Microsoft Technet article on the options available in Windows 7.
The javaw vs java application launcher
Once the java process can be initialized at Windows startup, one will get a console window that continues to stay around until the process is terminated. This occurs if the java executable is utilized to initialize the application.
From the technotes of the java application launcher:
The javaw command is identical to
java, except that with javaw there is
no associated console window. Use
javaw when you don't want a command
prompt window to appear. The javaw
launcher will, however, display a
dialog box with error information if a
launch fails for some reason.
Therefore, if you wish to avoid opening a console window for the Java process, you ought to use the javaw executable.
This is very simple. You will find the startup folder in the C:/Documents and Settings/AllUsers/YourUserName/StartUp. It will be on similar kind of path just check it. Then just paste your jar file in that folder and it will work nice. Remember that you put the jar file in the startup folder of your user name folder. You may find that this folders might be hidden so just check it out. If you find this answer useful vote it. Enjoy.....