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Cannot run 'python -c ".." ' command from Java Process builder and Linux

I was developing my spring boot server on Windows. Now I have upgraded to Ubuntu 20.04.
the project executes a python script which should return a result as a txt file with this command:
python3 -c "from main import *;main(function,'/tmp/execution12480676806364930620/executionResponse.txt')"
Thanks to this code:
List<String> items = Arrays.asList(project.getExecutorType().buildAndGetExecutionCommandByProject(project));
ProcessBuilder pb = new ProcessBuilder(items);
pb.directory(new File(project.getPath()));
Process p = pb.start();
p.waitFor(5, TimeUnit.SECONDS);
when I print in the console the array passed in the Item variable:
[python3, -c, "from main import *;main(function, '/tmp/execution12480676806364930620/executionResponse.txt')"]
and the path of the array passed in pb.directory :
/tmp/execution12480676806364930620
My problem is that the project is not running and returning nothing.
when i go to the folder and run the same command from terminal everything works.
And that on windows 10 this same process worked fine.
Looking at similar issues I modified my code like this but it doesn't change anything:
List<String> items = Arrays.asList(project.getExecutorType().buildAndGetExecutionCommandByProject(project));
ProcessBuilder pb = new ProcessBuilder();
pb.command(items);
pb.redirectErrorStream(true);
pb.directory(new File(project.getPath()));
Process p = pb.start();
p.waitFor(5, TimeUnit.SECONDS);
What am I doing wrong?
Edit :
My command for read outputs :
private String inputStreamToString(InputStream inputStream){
return new BufferedReader(
new InputStreamReader(inputStream, StandardCharsets.UTF_8)).lines()
.collect(Collectors.joining("\n"));
}
And I call it like that :
System.out.println(this.inputStreamToString(p.getErrorStream()));
System.out.println(this.inputStreamToString(p.getInputStream()));
What works, when I just run "python main.py" I get the errors and print them out.
I can easily add the command at the end of the main file but I don't understand why the python -c "..." is not working? I am not receiving any errors ... I manage several languages ​​and this could be a problem for me later

Aha! On closer inspection I think you're right it's not executing anything (and thus not producing any output either normal or error for you to see).
You don't show how the array of strings is created, but your printout suggests you have actually put quotemarks in the third string. That's wrong. When you give the shell command line python -c "import this; dothat" the shell uses the quotemarks to control parsing of this command line, but it does not pass them to the python process; the args passed to the python process (shown vertically for clarity, and omitting the argv[0]=program used in C but omitted in Java) are actually
-c
import this; dothat
If you pass an argument actually containing quotemarks like
-c
"import this; dothat"
then python doesn't execute the commands import and dothat; instead it evaluates the string literal "import this; dothat" and (since it isn't running interactively) discards the result.
Try not including, or removing, the " at the beginning and end. But leave the ' inside the string value because you do want python to receive those.

Can I get the real full executed command of Java Runtime.getRuntime().exec?

When I tried to run Ansible with Runtime.getRuntime().exec with Java
Here is what I did:
String[] cmd = {"ansible-playbook", "/path/to/playbook", "--extra-vars", "'{\"filePath\":\"/path/to/file\"}'"};
Process process = Runtime.getRuntime().exec(cmd, null);
I got error message like this:
FAILED! => {"failed": true, "msg": "'filePath' is undefined"}
However when I executed the same command with terminal:
ansible-playbook /path/to/playbook --extra-vars '{"filePath":"/path/to/file"}'
Everything was fine...
I think there must be some differences between the command I ran in terminal and Java, maybe apostrophe or quotation mark ?
I'm wondering is there any way to get the real executed command of Runtime.getRuntime().exec? Just like I can get command line history of some user by history...

You are adding additional quotes in your third parameter:
"'{\"filePath\":\"/path/to/file\"}'"
If you do this, you're not executing the same command in your shell as you have above. You're actually executing (in bash):
ansible-playbook /path/to/playbook --extra-vars ''\''{"filePath":"/path/to/file"}'\'''
You don't need the single quotes around the value here: because you're passing these values directly, you don't have to worry about the quoting that you'd have to do in a shell. You can simply use:
"{\"filePath\":\"/path/to/file\"}"

Run external app by userinput

So I'm creating a Java program and I want to make it so that you can ask it to open a program.
But, here's the catch, I want the program it opens to be taken from the user input, right now I'm trying to change this
try{Process p = Runtime.getRuntime().exec("notepad.exe");}
catch(Exception e1){}
Into something that opens a program that you asked it to open.
Here's an example of what I want:
User: Can you open chrome?
Program: Of course, here you go!
chrome opens
Could anyone tell me how I would be able to do this?

You can do it in two ways:
1.By Using Runtime:
Runtime.getRuntime().exec(...)
So, for example, on Windows,
Runtime.getRuntime().exec("C:\application.exe -arg1 -arg2");
2.By Using ProcessBuilder:
ProcessBuilder b = new ProcessBuilder("C:\application.exe", "-arg1", "-arg2");
or alternatively
List<String> params = java.util.Arrays.asList("C:\application.exe", "-arg1", "-arg2");
ProcessBuilder b = new ProcessBuilder(params);
or
ProcessBuilder b = new ProcessBuilder("C:\application.exe -arg1 -arg2");
The difference between the two is :
Runtime.getRuntime().exec(...)
takes a single string and passes it directly to a shell or cmd.exe process. The ProcessBuilder constructors, on the other hand, take a varargs array of strings or a List of strings, where each string in the array or list is assumed to be an individual argument.
So,Runtime.getRuntime.exec() will pass the line C:\application.exe -arg1 -arg2 to cmd.exe, which runs a application.exe program with the two given arguments. However, ProcessBuilder method will fail, unless there happens to be a program whose name is application.exe -arg1 -arg2 in C:.

You can try it with like. Pass whole path of where you install chrome.
try{
Process p = Runtime.getRuntime().exec("C:\\Program Files\\Google\\Chrome\\Application\\chrome.exe");
}
catch(Exception e1){
}

When using exec, it is essentially the same as if you were using the command line on windows. Open Command Prompt, type open, and see if it gives details as to how it opens files. If not, find the opener. Usually when dealing with command line operations, there are multiple parameters that are required for opening files/applications. An example of this would be for opening the "TextEdit.app" application on a mac.
Process p = Runtime.getRuntime().exec("open -a TextEdit.app");
Terminal(for mac) would open the app using the -a flag, meaning "application." You could open a file doing:
Process p = Runtime.getRuntime().exec("open filename.file_ext -a TextEdit.app");
The second one will tell the computer to find the application named <app_name>.app and open the file filename.file_ext
I know this is not going to work for a windows machine, but it's only to show how to use the command line operations for opening files and applications. It should be similar for windows though.
Hope this helps

Different output -- when running mathtext in command line and when the command is executed from a java program using apache-commons-exec

I am trying to run mathtext from a java program using apache-commons-exec. The problem is I am getting different output when I run the same command from a java program and when I run it through shell.
so if run mathtext like this in the shell:
./mathtext test.png "\$\frac{{\left( {{p^2} - {q^2}} \right)}}{2}\$"
in a shell I get the perfect png
but when I run the same thing using apache-commons-exec
Map map = new HashMap();
map.put("target", new File(trgtFileName));
DefaultExecuteResultHandler resultHandler = new DefaultExecuteResultHandler();
Executor exec = new DefaultExecutor();
exec.setWorkingDirectory(/*I set the working directory where the mathtext is*/);
CommandLine cl = new CommandLine("./mathtext");
cl.addArgument("${target}");
cl.addArgument(latex);
cl.setSubstitutionMap(map);
// Logger.log4j.info("command is:::"+cl.toString());
ExecuteWatchdog watchdog = new ExecuteWatchdog(5000);
exec.setWatchdog(watchdog);
exec.execute(cl,EnvironmentUtils.getProcEnvironment(),resultHandler);
resultHandler.waitFor();
I get the image, not the equation but the raw TeX string :(
Can somebody please help me in solving the issue? I want to get the exact output.
Thanks.

I figured out where the problem was:
$ is a special character for the unix shell and not for java. So even if in the command line the input needs to escape $ like:
"\$\frac{{\left( {{p^2} - {q^2}} \right)}}{2}\$"
inside the java program I dont need to escape the '$' or put " (double quotes) at the beginning and at the end.I had to put the command like:
$\frac{{\left( {{p^2} - {q^2}} \right)}}{2}$
Hope this helps somebody :)
--Shankhoneer

Java cannot execute system command (Ubuntu)

It's not the first time I have tried to execute a system command from Java; but this time it turns out to be very hard. I have a script that executes just fine from the terminal. It reads input from a file (input.txt), it processes it and exports the result in another file (ouput.txt). The whole thing lasts no more than 1sec. But, when I try to execute it from Java, it gets stuck and never finishes. This is my code:
Process p = new ProcessBuilder("./runCalculator.sh").start();
p.waitFor();
I have also tried with Runtime.getRuntime().exec("./runCalculator.sh") but all the same. I've read both the InputStream and the ErrorStream of the process. The error stream returns nothing but a message like "Starting Calculation..."
Any ideas?

You need to use the following code:
ProcessBuilder pb = new ProcessBuilder();
pb.command("bash", "-c", "./runCalculator.sh");
Process process = pb.start();
int retValue = process.waitFor();

You likely need to invoke the unix command interpreter/processor for this to work. Please see: When Runtime.exec() won't.

Try this:
Process p = new ProcessBuilder("sh ./runCalculator.sh").start();

Another, simplier solution is that you can open program by entering the name of the program (this assumes that program is installed) instead of creating script and calling it.
Note that the name of the program isn't always what you see in Gnome's menu, for example Gnome's calculator is "gnome-calculator". Regarding this facts, you can run calculator by the folowing line:
Process p = Runtime.getRuntime().exec("gnome-calculator");
In that case you don't have a need for any sh scripts (in your case runCalculator.sh).