Getting Linux Distro from java

Question

From java, I got name of the OS Iam working. See below code :

System.out.println(System.getProperty("os.name"));

In windows xp, it prints like : Windows XP

But in ubuntu/fedora, it shows only Linux.

Can anyone help me to find which linux version Iam using (like ubuntu or fedora) using java code? Is it possible to find the linux distro from java?

Answer 1

This code can help you:

String[] cmd = {
"/bin/sh", "-c", "cat /etc/*-release" };

try {
    Process p = Runtime.getRuntime().exec(cmd);
    BufferedReader bri = new BufferedReader(new InputStreamReader(
            p.getInputStream()));

    String line = "";
    while ((line = bri.readLine()) != null) {
        System.out.println(line);
    }
} catch (IOException e) {

    e.printStackTrace();
}

UPDATE

It if you only need the version try with uname -a

UPDATE

Some linux distros contain the distro version in the /proc/version file. Here is an example to print them all from java without invoking any SO commands

//lists all the files ending with -release in the etc folder
File dir = new File("/etc/");
File fileList[] = new File[0];
if(dir.exists()){
    fileList =  dir.listFiles(new FilenameFilter() {
        public boolean accept(File dir, String filename) {
            return filename.endsWith("-release");
        }
    });
}
//looks for the version file (not all linux distros)
File fileVersion = new File("/proc/version");
if(fileVersion.exists()){
    fileList = Arrays.copyOf(fileList,fileList.length+1);
    fileList[fileList.length-1] = fileVersion;
}       
//prints all the version-related files
for (File f : fileList) {
    try {
        BufferedReader myReader = new BufferedReader(new FileReader(f));
        String strLine = null;
        while ((strLine = myReader.readLine()) != null) {
            System.out.println(strLine);
        }
        myReader.close();
    } catch (Exception e) {
        System.err.println("Error: " + e.getMessage());
    }
}

Answer 2

Starting from this, I extending the code to include different fallback scenarios in order to get the OS versions on several platforms.

Windows is descriptive enough, you get the info from the 'os.name' system property

Mac OS : you need to keep a list of the release names according to the version

Linux : this is the most complicated, here is the list of fallbacks:
- get the info from the LSB release file if the distro is LSB compliant
- get the info from the /etc/system-release if it exists
- get the info from any file ending with '-release' in /etc/
- get the info from any file ending with '_version' in /etc/ (Mostly for Debian)
- get the info from /etc/issue if it exists
- worst case, get what info from /proc/version is available

You can get the utility class here:
https://github.com/aurbroszniowski/os-platform-finder

Answer 3

You can use java to run uname -r, and get the results; that usually reveals the distro unless it was compiled by some dude from source in his basement. For my machine:

mao@korhal ~ $ uname -r
3.4.9-gentoo

and to run it:

Process p = Runtime.getRuntime().exec("uname -r");  
BufferedReader in = new BufferedReader(  
                    new InputStreamReader(p.getInputStream()));  
String distro = in.readLine();  

// Do something with distro and close reader

Edit: perhaps uname -a would work better here for distros in general. Or look at /etc/*-release files, which seems to be generally defined on most generals.

Answer 4

One ad-hoc way of getting Linux distro name is to read the content of /etc/*-release file. It will give you something like CentOS release 6.3 (Final).

Reading content of this file from Java is straight forward.

Might not be the best way, but it will get the job done, also this works only on *nix box and not on windows.