Write an executable .sh file with Java for OSX
Solution 1
You'd need to chmod it, and you can probably do it by exec'ing a system command like such:
Really all you'd need is to fire off something like this:
Runtime.getRuntime().exec("chmod u+x "+FILENAME);
But if you want to keep track of it more explicitly can capture stdin / stderr then something more like:
Process p = Runtime.getRuntime().exec("chmod u+x "+FILENAME);
BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));
BufferedReader stdError = new BufferedReader(new InputStreamReader(p.getErrorStream()));
Which I got from here: http://www.devdaily.com/java/edu/pj/pj010016/pj010016.shtml
Update:
Test program:
package junk;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Writer;
public class Main{
private String scriptContent = '#!/bin/bash \n echo "yeah toast!" > /tmp/toast.txt';
public void doIt(){
try{
Writer output = new BufferedWriter(new FileWriter("/tmp/toast.sh"));
output.write(scriptContent);
output.close();
Runtime.getRuntime().exec("chmod u+x /tmp/toast.sh");
}catch (IOException ex){}
}
public static void main(String[] args){
Main m = new Main();
m.doIt();
}
}
On linux if you open up a file browser and double click on /tmp/toast.sh and choose to run it, it should generate a text file /tmp/toast.txt with the words 'yeah toast'. I assume Mac would do the same since it's BSD under the hood.
Solution 2
You can call File.setExecutable()
to set the owner's executable bit for the file, which might be sufficient for your case. Or you can just chmod
it yourself with a system call with Process
.
Alas, full-powered programmatic alteration of file permissions isn't available until Java 7. It'll be part of the New IO feature set, which you can read more about here.
Solution 3
In Java 7 you can call Files.setPosixFilePermissions
. Here is an example:
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.attribute.PosixFilePermission;
import java.util.Set;
class FilePermissionExample {
public static void main(String[] args) throws IOException {
final Path filepath = Paths.get("path", "to", "file.txt");
final Set<PosixFilePermission> permissions = Files.getPosixFilePermissions(filepath);
permissions.add(PosixFilePermission.OWNER_EXECUTE);
Files.setPosixFilePermissions(filepath, permissions);
}
}
Solution 4
On Mac OS X, besides chmod +x, you have to give a .command
extension to your shell script if you want to launch it with a double-click.
Solution 5
This answer I wrote for the question how do I programmatically change file permissions shows a chmod example via a native call using jna, which should work on Mac OS X.
Glenn
Updated on July 26, 2022Comments
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Glenn over 1 year
So I am trying to write an .sh file that will be executable, this is how I'm currently writing it:
Writer output = null; try { output = new BufferedWriter(new FileWriter(file2)); output.write(shellScriptContent); output.close(); } catch (IOException ex) { Logger.getLogger(PunchGUI.class.getName()).log(Level.SEVERE, null, ex); }
So that writes the file just fine, but it is not executable. Is there a way to change the executable status when I write it?
Edit: To further clarify, I am trying to make it execute by default, so that for instance, if you double clicked the generated file, it would automatically execute.
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Glenn over 14 yearsThanks for the suggestion! Will this also make it automatically execute when double clicked?
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user49913 over 14 yearsIt should, assuming the user running the java program is the same who will run the shell script. Otherwise you could adjust the chmod to a+x which means all users have execute permission. I did a small test program on linux and it worked for me.
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Glenn over 14 yearsThanks, but unfortunately, I'm working with 1.5. It has to have pretty broad compatibility for OSX, and most people don't have 1.6.
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redDragonzz almost 11 yearsYou saved the day dude, i was getting around how to execute a script from within java and turns out all i needed to do was make it executable via the
chmod
command ! Thanks