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Why is my runtime command ignored after calling a batch file?

public class Test_Python
{
public static void main( String[] args ) throws IOException
{
String command = "cmd /k start cmd.exe /k \"cd C:\\Workspace\\supply\\environment\\ && setup.bat && python -V ";
Runtime.getRuntime().exec(command);
}
}
When I execute my code, the "python -V" does not work, it is not executed in the cmd window.
But if I delete the "setup.bat" from my command, the "python -V" is executed (I can read the version in the cmd window)
Also, if I manually start a cmd, type setup.bat and then python -V it works.
My batch file is used to set my working environment:
SET basedir=%~dp0
echo %basedir%
cmd /k "cd %basedir%\..\scripts && set PYTHONPATH=%basedir%\..\lib"
Is there any way to know why it fails?

Unlike python Java may need some help. As I can see you are running on Windows.
You invoke the Runtime.exec() method. The method returns a Process instance, and in it's documentation you can read
By default, the created process does not have its own terminal or console. All its standard I/O (i.e. stdin, stdout, stderr) operations will be redirected to the parent process, where they can be accessed via the streams obtained using the methods getOutputStream(), getInputStream(), and getErrorStream(). The parent process uses these streams to feed input to and get output from the process. Because some native platforms only provide limited buffer size for standard input and output streams, failure to promptly write the input stream or read the output stream of the process may cause the process to block, or even deadlock.
So it is likely your process is started by the OS but gets blocked due to I/O restrictions. Get around that by reading the STDOUT and STDERR streams until your process finishes. One good programming model is visible at https://www.baeldung.com/run-shell-command-in-java
Now that we know the OS is not blocking the process, the issue may be inside the command itself. Note you concatenated several commands using the && operator. I do not have a windows system but searched a bit online:
https://www.ionos.com/digitalguide/server/know-how/windows-cmd-commands/
CommandA && CommandB (the second command is only run if the first was successful)
To check how the first part of your command exits run it separately in Java and do not forget to print the process.exitValue() method.
But looking at the whole picture, all you do with the first part is to change the working directory and set some environment variable. What stops you from running the ProcessBuilder methods? The example in the documentation directly sets the environment and directory.

Pass arguments and run .cmd file in windows using java

I want to run and pass the arguments to ".cmd" file using Java program. I have checked the existing Solutions, but nothing is working in my case.
From Command line, I am running below command after getting into Directory C:/users/project/solr/bin
solr.cmd -s "C:users/github/example/solr-config"
So, solr.cmd gets arguments from the other Directory and then it runs the solr instance.
I have tried this, but I am not sure how to provide Parameters to Runtime.getRuntime():
Runtime run = Runtime.getRuntime();
Process p = null;
String cmd = "cmd /c start C:/users/project/solr/bin C:users/github/example/solr-config";
Process pr = run.exec(cmd);
I have followed this link: How do I run a batch file from my Java Application?
Could anyone please help me this.

I solved it by modifying cmd as solr.cmd expects -s also as argument:
String cmd = "cmd /c start C:/users/project/solr/bin/solr.cmd -s C:users/github/example/solr-config;

There is a difference between "it doesn't work" and "it doesn't show anything". As per the documentation:
By default, the created subprocess does not have its own terminal or console. All its standard I/O (i.e. stdin, stdout, stderr) operations will be redirected to the parent process, where they can be accessed via the streams obtained using the methods getOutputStream(), getInputStream(), and getErrorStream(). The parent process uses these streams to feed input to and get output from the subprocess. Because some native platforms only provide limited buffer size for standard input and output streams, failure to promptly write the input stream or read the output stream of the subprocess may cause the subprocess to block, or even deadlock.
If you want to retrieve the data that your process might have printed out on the standard I/O, you will have to read them from the abovementioned streams.

Java Runtime.exec() with ssh on Linux Issues

I am trying to start a new process using Runtime.exec(), but my problem lies within using ssh to remote in and then run a java program there. Code:
test = "ssh -t username#host java packageName.ClassName portNumber (Other command line args for this class)"
Process proc = Runtime.getRuntime().exec(new String[] {"/bin/bash", "-c", test});
this doesn't fail or catch, but I need to be able to see the stdout for the newly running process and I don't.
Note: if I run ssh -t username#host java packageName.ClassName portNumber (Other command line args for this class) from the command line it works fine. I have the host setup to not require a password by using ssh keys.
Any ideas?

You need to use Process.getInputStream to obtain the output from the sub-process being created.
See this article for a good discussion on Runtime.exec.

I think you can ask for an input stream that corresponds to the stdout of the process and then print it on your standard output. If you need to see it after it executes, just call waitFor() method on the process so it finishes before you start printing.

Use getInputStream() to access returned process's stdout. You can also use facilities provided by ProcessBuilder.Redirect.

How can I run a bash script (which downloads a file) in Java?

Running in Mac OS X Lion, I need to retrieve a file from a remote server using a script in the command line. The command I'm trying to use in code is "bash /my/path/here/myscript" and I already run another process from the command line (atos) using the code below.
Process proc = Runtime.getRuntime().exec(cmd);
But while debugging, the program continues without error, yet the script does appear to have actually run. Furthermore, there should be a pause of several seconds while the script retrieves the file, yet my program continues to execute immediately. The script itself works as intended when run from the terminal. I'm a little stumped on how to get this to work, so any help would be greatly appreciated.

Got it to work with the following code -
Process proc = Runtime.getRuntime().exec(cmd);
BufferedReader in = new BufferedReader(new InputStreamReader(proc.getInputStream()));
proc.waitFor();
while (in.ready()) {
System.out.println(in.readLine());
}
The other thing that was an issue is that the script would download to the current working directory rather than the location of the script itself (as intended). So the script would run correctly while my program would continue to fail to find the downloaded file. Hope this helps.

Powershell process hanging when called from Java application

I am trying to write a simple application that takes in a command line arguement (which will be a Powershell ps1 file) and then run it. So I have experemented with a number of different approaches and seem to be running into a problem. If I attempt to invoke powershell from within java, the windows process is started and is visible via process explorer, however powershell never returns, it hangs in some sort of loop by the looks of it. The command I am using is:
String command = "powershell -noprofile -noninteractive \"&C:\\new\\tst.ps1\"";
The command is then executed using:
Runtime systemRuntime = Runtime.getRuntime();
Process proc = systemRuntime.exec(command);
At the moment I am hard coding the location to the ps1 file as I was trying to rule this out as an issue. Using a process explorer I can see the hanging powershell process and the command that was passed to it was :
powershell -noprofile -noninteractive "&C:\new\tst.ps1"
which when copied into a cmd window, works to launch the tst.ps1 file. The file itself is incredibly simple in this example and I think I can rule it out being the cause of the freeze as I have tried to launch other ps1 files the same behaviour can be seen.
To further add to the confusion, if I use the java code posted above and pass in powershell commands instead of a file name then it successfully runs.
I've scoured the web and see lots of people experiencing the same issue but no one seems to have posted there solution, I hope its a simple oversight on my part and can be easily fixed.
Any hints/tips are appreciated :D
Alan

You have to close OutputStream in order for Powershell to exit.
Runtime systemRuntime = Runtime.getRuntime();
Process proc = systemRuntime.exec(command);
proc.getOutputStream().close();

Is your external program writing to the standard outputs (err and out)?
If yes, it can hang waiting for you to consume them from the java parent process.
You can get those as InputStreams by calling
Process.getInputStream()
and
Process.getErrorStream()
There's more details here:
Javadoc for Process