I work on a Macbook and I would like to close some running applications such as Remote Desktops through using Java.
I'm quite new to programming in Java and other than Google and StackOverflow I'm not sure where to go. I already looked for a solution on Google but all I can find are instruction on how to close Java on Mac OS, not actually how you close a running application through Java code.
So I am looking for some pointers on what Java commands I should use to close a running application in Mac OS. Thank you very much :)
While programming in Java, you only have access to do things inside the JVM. But your code inside the JVM wouldn't usually have permissions to affect other processes running on the operating system.
You can definitely call an external command with something like this:
Process process = Runtime.getRuntime().exec("kill 12345");
That would run the kill command on process id 12345. This would work, assuming you have the right permissions.
You can get more information on the exec command in the docs: https://docs.oracle.com/javase/7/docs/api/java/lang/Runtime.html#exec(java.lang.String)
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I have a java program that should run on a Windows machine. It should run "forever", i.e. when the JVM or the program crashes, it should be restarted. When the computer is restarted it should also be restarted.
I saw advice to wrap the program as a "Windows service", but the tools I found seem to be either costly, complicated or outdated.
Can somebody describe me a straightforward way to achieve the desired behaviour?
For the part where you want to start the program after restart you can create a simple batch (.Bat) file and u can put that file in the startup folder.
Also you can use the same file for running the program when it crashes. you can use tasklist command and check if your java program is running and if it is not .just start the program.
Just check our windows batch this is one of the best things you can get everything for doing anything on windows without anything expensive
Yet Another Java Service Wrapper is a tool that easily wraps your Java program into a Windows service. Just start the program, note down the PID and enter it into the wrapper. Two things, which are probably universal to services, should be noted:
For connection to the network, you need to specify an account with the necessary rights.
Connected network drives are not available.
I need a Java way to find a running OS process from which I know to name and path of the executable. I want to look whether it is running right now and I need a way to kill the process if I found it.
My Question is a similar to how-to-find-and-kill-running-win-processes-from-within-java but not restricted to windows.
Am I forced to do an implementation per platform or is there some trick/library/api I'm missing that can do this?
The SIGAR library has some pretty cool support for stuff like this. It has java APIs for listing and killing system processes.
I'm writing a program which monitors Java Applications. I'd like to monitor the state of the native processes and know when they exit. This is fine; Java gives me the Process object and I can waitFor() on it.
However, the problem that arises is that if my program dies, I would like it to get the reference to the process back - which it can't do in Java because it never created the process. My first guess was to send the process object over RMI and have the client app send it back when a reconnection occurs, but that won't work because Process isn't serializable.
I can think of a way to do this natively using JNA on Windows, but does anyone know if there is an existing library which will do this?
Cheers!
You can use WMI to implement this on Windows and command line utilities on Unix (if you need).
I know the following tools to work with WMI: JaWin, WIntegra, JInterop.
If your monitor is running in windows too you can use JaWin. It is a JNI wrapper over COM+ API. If you want to be cross platform and be able to monitor Windows machine from Unix machine use JInterop. It is open-source library that implements DCOM protocol in pure java. JIntegra is similar but commercial.
EDIT: probably even simpler solution. If you want to monitor java application just use JMX. Connect to this application using JMX either remotely or locally.
Good luck.
Is it possible to stop an application in windows using java code ?
I'd like to create a program which is like a shortcut to stop an application on my pc. Is it possible using ProcessBuilder ? Thank you
Plain Java, without native access? No.
ProcessBuilder lets you control processes that you started from within the Java application, but it doesn't give you control to processes that were started by other processes.
As per user988052's comment, you can use pskill from the Sysinternals Suite to accomplish this through Runtime.exec. pskill uses the TerminateProcess function call. You can also call this function with JNI (or some other native caller, like JNA, NLink, etc.), but you'll need to obtain a handle to the process via the OpenProcess function call.
Is it possible to stop an application in windows using java code ? ... Is it possible using ProcessBuilder ?
Only if you launched the application from the same Java application that you are trying to fill it from.
Other than that, you need to resort to running a Windows-specific command to do the killing ... or something based on JNI to make native Windows library calls.
The other complications are that you may not be able to kill certain processes due to permissions issues, and some process may refuse to be killed.
I believe the JRE does not provide an API for system processes. ProcessBuilder can create system processes, but it cannot provide you with a Process object for a process created outside the JVM. I believe that is a philosophical decision on the part of the Java folks, to avoid certain OS-specific tasks where possible. You might think that every OS has pids, or that they all have some kind of kill message, but Java runs on lots of OSes, some of them quite strange.
You could make native code to do it and wrap that with JNI, but that would be wasteful. As Mr 988052 says, I suggest you execute a system-specific command through Runtime.exec or ProcessBuilder. You would need to decide which OSes you want to support, and be sure to get the commands (and the OS-detection code) right for each one.
I am running my java application where i have used threads...
i am running this application using ant command on the terminal..
But when i close my terminal or press ctrl+c,then java program which was running stops...
Please help me out to solve this as i want to run this program continously...
If you kill the Java process, Java will no longer be running. If you want the threads to keep running continuously, the Java program must remain active.
Invoking such a program with ant is not usually the way to do it. On Unix-like systems, you would typically run such a program in the background via /etc/init.d startup scripts. In Windows the equivalent would be starting your program as a service, though I'm not sure of the intricacies involved in getting Java to run this way.
If you're running something from a concole - how about just not killing it and minimising the console? If you're starting it from Linux (or Cygwin) just append a & to the end of the command line and the process will run in the background.
Tell us more about your environment, and what compromises you're prepared to put up with (e.g. having a minimised console window sit in the taskbar) and we can help you more. At the moment, the only definitive answer I can give is that "yes - Ctrl-C will kill your program (as intended). If you want it to keep running, don't tell it to stop running." :-)
You can run your application as a service in linux or windows.
Have a look at the screen command for Linux.
I guess this is desired behavior. If you terminate your application, It gets shut down.
If you wish to run the application in the background you should consider making it a windows service or a deamon.
If you wish to continue running it as a application on *nix, you can consider to use GNU Screen.
Run the ant command in the background and redirect its output to a file:
ant &> my.log &.
NB: this issue does not seems thread related (unless I've misunderstood it).
It sounds like you want to daemonize your ant task. I'd suggest the following command:
nohup ant &> ant.log < /dev/null &
The nohup will allow the program to continue to run after you close the terminal.
I'm surprised nobody has mentioned the all-too-famous Java Service Wrapper. This is an excellent piece of software if you are developing long-running processes (a.k.a services).