How to get a list of current open windows/process with Java?

Question

Does any one know how do I get the current open windows or process of a local machine using Java?

What I\'m trying to do is: list the current open task, windows or

Answer 1

The below program will be compatible with Java 9+ version only...

To get the CurrentProcess information,

public class CurrentProcess {
    public static void main(String[] args) {
        ProcessHandle handle = ProcessHandle.current();
        System.out.println("Current Running Process Id: "+handle.pid());
        ProcessHandle.Info info = handle.info();
        System.out.println("ProcessHandle.Info : "+info);
    }
}

For all running processes,

import java.util.List;
import java.util.stream.Collectors;

public class AllProcesses {
    public static void main(String[] args) {
        ProcessHandle.allProcesses().forEach(processHandle -> {
            System.out.println(processHandle.pid()+" "+processHandle.info());
        });
    }
}

Answer 2

This is another approach to parse the the process list from the command "ps -e":

try {
    String line;
    Process p = Runtime.getRuntime().exec("ps -e");
    BufferedReader input =
            new BufferedReader(new InputStreamReader(p.getInputStream()));
    while ((line = input.readLine()) != null) {
        System.out.println(line); //<-- Parse data here.
    }
    input.close();
} catch (Exception err) {
    err.printStackTrace();
}

If you are using Windows, then you should change the line: "Process p = Runtime.getRun..." etc... (3rd line), for one that looks like this:

Process p = Runtime.getRuntime().exec
    (System.getenv("windir") +"\\system32\\"+"tasklist.exe");

Hope the info helps!

Answer 3

    String line;
    Process process = Runtime.getRuntime().exec("ps -e");
    process.getOutputStream().close();
    BufferedReader input =
            new BufferedReader(new InputStreamReader(process.getInputStream()));
    while ((line = input.readLine()) != null) {
        System.out.println(line); //<-- Parse data here.
    }
    input.close();

We have to use process.getOutputStream.close() otherwise it will get locked in while loop.

Answer 4

package com.vipul;

import java.applet.Applet;
import java.awt.Checkbox;
import java.awt.Choice;
import java.awt.Font;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

public class BatchExecuteService extends Applet {
    public Choice choice;

    public void init() 
    {
        setFont(new Font("Helvetica", Font.BOLD, 36));
        choice = new Choice();
    }

    public static void main(String[] args) {
        BatchExecuteService batchExecuteService = new BatchExecuteService();
        batchExecuteService.run();
    }

    List<String> processList = new ArrayList<String>();

    public void run() {
        try {
            Runtime runtime = Runtime.getRuntime();
            Process process = runtime.exec("D:\\server.bat");
            process.getOutputStream().close();
            InputStream inputStream = process.getInputStream();
            InputStreamReader inputstreamreader = new InputStreamReader(
                    inputStream);
            BufferedReader bufferedrReader = new BufferedReader(
                    inputstreamreader);
            BufferedReader bufferedrReader1 = new BufferedReader(
                    inputstreamreader);

            String strLine = "";
            String x[]=new String[100];
            int i=0;
            int t=0;
            while ((strLine = bufferedrReader.readLine()) != null) 
            {
        //      System.out.println(strLine);
                String[] a=strLine.split(",");
                x[i++]=a[0];
            }
    //      System.out.println("Length : "+i);

            for(int j=2;j<i;j++)
            {
                System.out.println(x[j]);
            }
        }
        catch (IOException ioException) 
        {
            ioException.printStackTrace();
        }

    }
}

   You can create batch file like 

TASKLIST /v /FI "STATUS eq running" /FO "CSV" /FI "Username eq LHPL002\soft" /FI "MEMUSAGE gt 10000" /FI "Windowtitle ne N/A" /NH

Answer 5

The only way I can think of doing it is by invoking a command line application that does the job for you and then screenscraping the output (like Linux's ps and Window's tasklist).

Unfortunately, that'll mean you'll have to write some parsing routines to read the data from both.

Process proc = Runtime.getRuntime().exec ("tasklist.exe");
InputStream procOutput = proc.getInputStream ();
if (0 == proc.waitFor ()) {
    // TODO scan the procOutput for your data
}

Answer 6

Finally, with Java 9+ it is possible with ProcessHandle:

public static void main(String[] args) {
    ProcessHandle.allProcesses()
            .forEach(process -> System.out.println(processDetails(process)));
}

private static String processDetails(ProcessHandle process) {
    return String.format("%8d %8s %10s %26s %-40s",
            process.pid(),
            text(process.parent().map(ProcessHandle::pid)),
            text(process.info().user()),
            text(process.info().startInstant()),
            text(process.info().commandLine()));
}

private static String text(Optional<?> optional) {
    return optional.map(Object::toString).orElse("-");
}

Output:

    1        -       root   2017-11-19T18:01:13.100Z /sbin/init
  ...
  639     1325   www-data   2018-12-04T06:35:58.680Z /usr/sbin/apache2 -k start
  ...
23082    11054    huguesm   2018-12-04T10:24:22.100Z /.../java ProcessListDemo