How to get list of current running application like Task Manager except applications running in background using JAVA?

Question

How to get list of current running application like Task Manager except applications running in background using JAVA? I have this code i found - https://stackoverflow.com/a/41634959/11297873 :

 Process process = new ProcessBuilder("tasklist.exe", "/fo", "csv", "/nh").start();
    new Thread(() -> {
        Scanner sc = new Scanner(process.getInputStream());
        if (sc.hasNextLine()) sc.nextLine();
        while (sc.hasNextLine()) {
            String line = sc.nextLine();
            String[] parts = line.split(",");
            String unq = parts[0].substring(1).replaceFirst(".$", "");
            String pid = parts[1].substring(1).replaceFirst(".$", "");
            System.out.println(unq + " " + pid);
        }
    }).start();
    process.waitFor();
    System.out.println("Done");

I do not want to show background application like System, Windows, Intel etc....

Answer 1

You need here the powershell cmdlet called Get-Process .

   Process process = new ProcessBuilder("powershell","\"gps| ? {$_.mainwindowtitle.length -ne 0} | Format-Table -HideTableHeaders  name, ID").start();
        new Thread(() -> {
            Scanner sc = new Scanner(process.getInputStream());
            if (sc.hasNextLine()) sc.nextLine();
            while (sc.hasNextLine()) {
                String line = sc.nextLine();
                System.out.println(line);
            }
        }).start();
    process.waitFor();
    System.out.println("Done");

The output would be like this:

ApplicationFrameHost 15592
chrome               12920
cmd                  21104
debian               13264
Far                   3968
firefox              17240
HxOutlook             4784
idea64               13644
MicrosoftEdge         8024
MicrosoftEdgeCP      13908
MicrosoftEdgeCP      14604
mstsc                24636
notepad++             9956
OUTLOOK               9588
pycharm64             6396
rider64              10468
Teams                11540
Telegram             16760


Done

Answer 2

So i took your code

Process process = new ProcessBuilder("tasklist.exe", "/fo", "csv", "/nh").start();
    new Thread(() -> {
        Scanner sc = new Scanner(process.getInputStream());
        if (sc.hasNextLine()) sc.nextLine();
        while (sc.hasNextLine()) {
            String line = sc.nextLine();
            String[] parts = line.split(",");
            String unq = parts[0].substring(1).replaceFirst(".$", "");
            String pid = parts[1].substring(1).replaceFirst(".$", "");
            System.out.println(unq + " " + pid);
        }
    }).start();
    process.waitFor();
    System.out.println("Done");

And changed it to

Process process = new ProcessBuilder("tasklist.exe", "/fo", "csv", "/nh").start();
    new Thread(() -> {
        Scanner sc = new Scanner(process.getInputStream());
        if (sc.hasNextLine()) sc.nextLine();
        while (sc.hasNextLine()) {
            String line = sc.nextLine();
            String[] parts = line.split(",");
            String unq = parts[0].substring(1).replaceFirst(".$", "");
            String pid = parts[1].substring(1).replaceFirst(".$", "");
            System.out.println(line);
        }
    }).start();
    process.waitFor();
    System.out.println("Done");

essentially printing the entire line instead of just "unq" and "pid"

what i saw was that the entire printed line looked like this:

"System Idle Process","0","Services","0","8 K"

first 2 strings beeing "unq" and "pid" , while 3rd string is the specification of the process and the 5th string is how much memory it uses.

For what i could tell it seems like the 4th string might be what you are looking for. it always is either 0 or 1 and from what i could tell foreground processes always had a 1 therefore i assume if you check for it to be 0 you can get your background processes like this:

Process process = new ProcessBuilder("tasklist.exe", "/fo", "csv", "/nh").start();
    new Thread(() -> {
        Scanner sc = new Scanner(process.getInputStream());
        //if (sc.hasNextLine()) sc.nextLine();
        while (sc.hasNextLine()) {
            String line = sc.nextLine();
            String[] parts = line.split(",");
            String unq = parts[0].substring(1).replaceFirst(".$", "");
            String pid = parts[1].substring(1).replaceFirst(".$", "");
            if(parts[3].substring(1).replaceFirst(".$", "").equals("0")) {
                System.out.println(unq + " " + pid);
            }

        }
    }).start();
    process.waitFor();
    System.out.println("Done");

still not 100% sure and i couldnt find much by googling. but so far it seems like this could be the case