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Java Process Builder not executing multiple commands

Hi a Java newbie here.
I am currently building a Java application that executes multiple linux commands with Java Process builder.
I am planning to execute a shell scipt, and since it this shell script is an external program that takes about a second to fully execute, let the process sleep for a second and write the result into a txt file.
This is an external program and it must take in "q" to exit the program, so I finally need to type in q in the terminal.
I have gotten help on this community before and the code I constructed with that help is as follows.
public static void Linux(String fileName){
try {
File dir = new File("/usr/local/bin");
ProcessBuilder pb = new ProcessBuilder(new String[]{"/bin/bash", "-c", "./test_elanprv2.2.sh > \"$1\"; sleep 1; q", "_", fileName + ".txt"});
System.out.println("wrote text");
pb.directory(dir);
Process start = pb.start();
start.destroy();
}catch (Exception e){
e.printStackTrace();
System.out.println("failed to write text");
}
The process builder does create a txt file but it seems to be empty, and no matter how long I set the sleep to, the programs seems to instanly return the print statement.
It would really be appreciated if anyone could tell me what I am doing wrong.
Thank you in advance!!

As mentioned by #VGR, try using redirectOutput
public static void Linux(String fileName){
try {
File dir = new File("/usr/local/bin");
ProcessBuilder pb = new ProcessBuilder(new String[]{"/bin/bash", "-c", "./test_elanprv2.2.sh");
File output = new File("_", fileName + ".txt");
pb.redirectOutput(output);
System.out.println("wrote text");
pb.directory(dir);
Process start = pb.start();
start.destroy();
} catch (Exception e) {
e.printStackTrace();
System.out.println("failed to write text");
}

Most of your issues are due to a misunderstanding of how processes work. These concepts are not Java concepts; you would have the same issues in any other language.
First, you are destroying your process before it runs, and possibly before it even gets started. This is because pb.start() starts the process, and then you immediately destroy it without giving it a chance to complete.
You shouldn’t need to destroy the process at all. Just let it finish:
Process start = pb.start();
start.waitFor();
All processes have their own standard input and standard output. Again, this is not a Java concept; this has been a fundamental feature in Unix and Windows operating systems for a long time.
Normally, when a process prints information by writing it to its standard output. That is in fact what Java’s System.out.println does. In Unix shells (and in Windows), the > character redirects the standard output of a process to a file; the program still writes to its standard output, without ever knowing that the operating system is sending that output to a destination other than the terminal. Since it’s a fundamental operating system function, Java can do it for you:
ProcessBuilder pb =
new ProcessBuilder("/bin/bash", "-c", "./test_elanprv2.2.sh");
pb.redirectOutput(new File(fileName + ".txt"));
Similarly, when a process wants to take input, it normally does so by reading from its standard input. This is not the same as executing another command. When you do this:
./test_elanprv2.2.sh > "$1"; sleep 1; q
You are not sending q to the shell script. The above commands wait for the shell script to finish, then execute a sleep, then try to execute a program named q (which probably doesn’t exist).
Since the test_elanprv2.2.sh shell script probably accepts commands by reading its standard input, you want to send the q command to the standard input of that process:
ProcessBuilder pb =
new ProcessBuilder("/bin/bash", "-c", "./test_elanprv2.2.sh");
pb.redirectOutput(new File(fileName + ".txt"));
Process start = pb.start();
Thread.sleep(1000);
try (Writer commands = new OutputStreamWriter(start.getOutputStream())) {
commands.write("q\n");
}
// Caution: Call this AFTER writing commands. You don't want to write
// to the standard input of a process that has already finished!
start.waitFor();

Run batch file code from java code

I want to execute a batch file code from java button click. Also I don't want any command prompt window to be shown all from java code.
I have a code :-
C:\xyz-3.1.1\bin>dita --input=C:/Users/india/Desktop/mobile-phone/m
obilePhone.xyz --format=pdf --output=C:/Users/india/Desktop --logfile=C:/Use
rs/india/Desktop/dofhdif.txt
So I want above code to be run from batch command with C:\xyz-3.1.1\bin> as the parent directory.
Also I want to update --input file path whenever I will choose new file from JFileChooser.
I did this from the java code on button click transform:-
ProcessBuilder pb=new ProcessBuilder("dita --input=C:/Users/india/Desktop/mobile-phone/mobilePhone.xyz --format=pdf --output=C:/Users/india/Desktop --logfile=C:/Users/india/Desktop/dofhdif.txt");
pb.redirectErrorStream(true);
Process process=pb.start();
and getting IOException error.
I get stuck over here for long time , where am I going wrong.
EDIT :- error
java.io.IOException: Cannot run program "dita --input=C:/Users/india/Desktop/mobile-phone/m
obilePhone.xyz --format=pdf --output=C:/Users/india/Desktop --logfile=C:/Use
rs/india/Desktop/dofhdif.txt": CreateProcess error=2, The system cannot find the file specified
at java.lang.ProcessBuilder.start(Unknown Source)

As the Error mentioned, it cannot locate the command because the whole string will be treated as the command by ProcessBuilder.
Try to use Runtime.getRuntime().exec directly, but you have to ensure the command dita can be found.
Process process = Runtime.getRuntime().exec("C:\xyz-3.1.1\bin>dita --input=C:/Users/india/Desktop/mobile-phone/mobilePhone.xyz --format=pdf --output=C:/Users/india/Desktop --logfile=C:/Users/india/Desktop/dofhdif.txt");
process.waitFor();
int exitCode = process.exitValue();
System.out.println(IoHelper.output(process.getInputStream())); // handle the output;
Before JDK 5.0, the only way to start a process and execute it, was to use the exec() method of the java.lang.Runtime class after which ProcessBuilder can be used to help create operating system processes.
The major improvement being that, it also acts as a holder for all those attributes that influence the process. And this is how it should be used:
ProcessBuilder pb = new ProcessBuilder("myCommand", "myArg1", "myArg2");
P.S. Actually Runtime.getRuntime().exec can also be used with String... as:
Runtime.getRuntime().exec(new String[]{"curl", "-v", "--cookie", tokenString, urlString});
My personal preference:
If you have to configure the environment for the command: to control the working directory or environment variables and also you want to execute the commands several times, you'd better use it since the ProcessBuilder will hold the settings and what you need to do is just processBuilder.start() to create another process with the same settings;
If you want to execute a whole long string command as you mentioned, you'd better just use Runtime.getRuntime().exec since you can just execute it right there without any bothering of the parameter format.

Try this:
String inputFile = ...;
String outputFile = ...;
String logFile = ...;
ProcessBuilder pb = new ProcessBuilder(
"dita",
"--input=" + inputFile,
"--format=pdf",
"--output=" + outputFile,
"--logfile=" + logFile)
.directory(new File("C:\\xyz-3.1.1\\bin"))
//.inheritIO();
.redirectErrorStream(true);
Process process = pb.start();
This shows the following points:
The command is separated from the arguments
The argument values can be determined at runtime
The command's default directory (C:\xyz-3.1.1\bin) is set before starting the process
Consider using inheritIO() instead of redirectErrorStream() if you want the process's output to appear as part of your Java application's output.

ProcessBuilder: Start .jar in java package

I try to execute an external jar in my java application. The .jar is in my java-package ("gui").
I tried:
String filepath = this.getClass().getResource("ServerRSS.jar").getPath();
ProcessBuilder pb = new ProcessBuilder("java", filepath);
System.out.println(filepath); results in:
/C:/Users/hox/workspace/PraktikumProg/bin/gui/ServerRSS.jar
My programm doesn't start. Could the problem be the slash before the C: ?
EDIT:
The solution was:
URL filepath = this.getClass().getResource("ServerRSS.jar");
ProcessBuilder pb;
pb = new ProcessBuilder("java", "-jar", new File(filepath.toURI()).toString());
Process p = pb.start();

First get your command working ... simply on the command line.
And only then try to run it from within Java using a ProcessBuilder.
Simple answer is probably: to use -jar when invoking java.
java someJar.jar
does not work!
And yes, that slash matters big time. You simply want a fully correct file path there.
Finally: are you really sure you want to start a new JVM in order to run a main method in some class? You see, you could do that within your current JVM - without the additional performance and complexity cost of using a second JVM!

Java: run executable program whit particular parameters

I need to run executable progam (.exe) in java. This program have two different operating modes: GUI and Command line. The syntax to launch the program from the command line is as follows :
C:\Users\Ermanno\Desktop\ "programFolder"\"program.exe" /stext output.txt
in this way the program store the outoput in the file "output.txt".
I tired it:
Process p = new ProcessBuilder("C:\\Users\\Ermanno\\Desktop\\programFolder\\program.exe" ,"/stext a.txt").start();
does not create the output file.
I also tired to use a file batch that contains the command and run it to java but the result is the same.

You need to pass each argument in a single string:
... program.exe", "/stext", "a.txt")...
Also make sure that you start a background thread which reads the output of the child process. If there is a problem, then the child will print an error message to it's standard output and if you don't actively read it, then this output will be lost.
For this, loop over the streams p.getInputStream() and p.getErrorStream().
The latter is especially important since you say "I also tired to use a file batch". Java doesn't do anything different than a batch script. If you can't run the command from batch, it won't work from Java, either.

My experience was horrible with using the JDK ProcessBuilder and Runtime.getRuntime().exec. I then moved to Apache commons-exec. Here is an example:
String line = "AcroRd32.exe /p /h " + file.getAbsolutePath();
CommandLine cmdLine = CommandLine.parse(line);
DefaultExecutor executor = new DefaultExecutor();
int exitValue = executor.execute(cmdLine);

I solved using file bath. This file contains the command.
String [] _s = {"cmd.exe", "/c", "start", "file.bat"};
Process pr = Runtime.getRuntime().exec(_s);

Can't launch .exe from Java

I am trying to launch a .exe file through a Java program. I used the following code:
System.out.println("Opening " + path);
Process exec;
exec = Runtime.getRuntime().exec("rundll32 SHELL32.DLL,ShellExec_RunDLL " + path);//path is the path of the exe file which is passed as an argument from another java class
the output is as follows:
Opening C:\Program Files (x86)\C-Free 5\CppIDE.exe
But it is not opening.
Instead when I try
String pat="C:\\Program Files (x86)\\C-Free 5\\CppIDE.exe";
Process exec;
exec = Runtime.getRuntime().exec("rundll32 SHELL32.DLL,ShellExec_RunDLL " + pat);
the program is opened.
I don't know what the problem is.

It's very likely that the space in your path is the problem.
I suggest you pass the arguments as an array instead of passing a single string containing the whole command (alternatively you could quote the spaces correctly, but that's not quite as easy).
Either
use the String[] version of Runtime.exec() or
switch to using ProcessBuilder which has an altogether simpler and more intuitive API.
With ProcessBuilder this could look like this:
ProcessBuilder pb = new ProcessBuilder("rundll32", "SHELL32.DLL,ShellExec_RunDLL", path);
Process p = pb.start();
Also, I see no reason to invoke rundll32 at all in this scenario. This should work just as well:
ProcessBuilder pb = new ProcessBuilder(path);
Process p = pb.start();

You need to construct the path using File.separator. The path separator you are using will, in this case, will be system dependant.