Problem while running dos command from java program

Question

Dear friends,
I need to terminate a running jar file from my java program which is running in the windows os.
For that i have an dos command to find process id of java program and kill by using tskill command.
Command to find process id is,
wmic /output:ProcessList.txt process where "name='java.exe'" get commandline,processid
This command gives the ProcessList.txt file and it contains the processid. I have to read this file to find the processid.
when i execute this command in dos prompt, it gives the processid in the ProcessList.txt file. But when i execute the same command in java program it keeps running mode only.
Code to run this command is,
public class KillProcess {
     public static void main(String args[]) {
          KillProcess kProcess = new KillProcess();
          kProcess.getRunningProcess();
          kProcess = new KillProcess();
          kProcess.readProcessFile();
     public void getRunningProcess() {
          String cmd = "wmic /output:ProcessList.txt process where \"name='java.exe'\" get commandline,processid";
          try {
               Runtime run = Runtime.getRuntime();
               Process process = run.exec(cmd);
               int i = process.waitFor();
               String s = null;
               if(i==0) {
                    BufferedReader stdInput = new BufferedReader(new
                           InputStreamReader(process.getInputStream()));
                    while ((s = stdInput.readLine()) != null) {
                     System.out.println("--> "+s);
               } else {
                    BufferedReader stdError = new BufferedReader(new
                           InputStreamReader(process.getErrorStream()));
                    while ((s = stdError.readLine()) != null) {
                     System.out.println("====> "+ s);
               System.out.println("Running process End....");
          } catch(Exception e) {
               e.printStackTrace();
     public String readProcessFile() {
          System.out.println("Read Process File...");
          File file = null;
          FileInputStream fis = null;
          BufferedReader br = null;
          String pixieLoc = "";
          try {
               file = new File("ProcessList.txt");
               if (file.exists() && file.length() > 0) {
                    fis = new FileInputStream(file);
                    br = new BufferedReader(new InputStreamReader(fis, "UTF-16"));
                    String line;
                    while((line = br.readLine()) != null)  {
                         System.out.println(line);
               } else {
                    System.out.println("No such file");
          } catch (Exception e) {
               e.printStackTrace();
          return pixieLoc;
}     when i remove the process.waitFor(), then while reading the ProcessList.txt file, it says "No such file".
if i give process.waitFor(), then it's in running mode and program is not completed.
Colud anyone please tell me how to handle this situation?
or Is there anyother way to kill the one running process in windows from java program?
Thanks in advance,
Sathish

Answer 1

Hi masijade,
The modified code is,
class StreamGobbler extends Thread
    InputStream is;
    String type;
    StreamGobbler(InputStream is, String type)
        this.is = is;
        this.type = type;
    public void run()
        try
            InputStreamReader isr = new InputStreamReader(is, "UTF-16");
            BufferedReader br = new BufferedReader(isr);
            String line=null;
            while ( (line = br.readLine()) != null)
                System.out.println(type + ">" + line);
            } catch (IOException ioe)
                ioe.printStackTrace(); 
public class GoodWindowsExec
    public static void main(String args[])
        try
            String osName = System.getProperty("os.name" );
            String[] cmd = new String[3];
             if( osName.equals( "Windows 95" ) )
                cmd[0] = "command.com" ;
                cmd[1] = "/C" ;
                cmd[2] = "wmic process where \"name='java.exe'\" get commandline,processid";
            } else {
                cmd[0] = "cmd.exe" ;
                cmd[1] = "/C" ;
                cmd[2] = "wmic process where \"name='java.exe'\" get commandline,processid";
            Runtime rt = Runtime.getRuntime();
            System.out.println("Execing " + cmd[0] + " " + cmd[1]
                               + " " + cmd[2]);
            Process proc = rt.exec(cmd);
            System.out.println("Executing.......");
            // any error message?
            StreamGobbler errorGobbler = new
                StreamGobbler(proc.getErrorStream(), "ERROR");           
                      // any output?
          StreamGobbler outputGobbler = new
                StreamGobbler(proc.getInputStream(), "OUTPUT");
                      // kick them off
            errorGobbler.start();
            outputGobbler.start();
            // any error???
            int exitVal = proc.waitFor();
            System.out.println("ExitValue: " + exitVal);       
        } catch (Throwable t)
            t.printStackTrace();
}when i execute the above code, i got output as,
Execing cmd.exe /C wmic process where "name='java.exe'" get commandline,processid
and keeps in running mode only.
If i execute the same command in dos prompt,
CommandLine
ProcessId
java -classpath ./../lib/StartApp.jar;./../lib; com.abc.middle.startapp.StartAPP  2468
If i modify the command as,
cmd.exe /C wmic process where "name='java.exe'" get commandline,processid  > 123.txt
and keeps in running mode only.
If i open the file when program in running mode, no contents in that file.
If i terminte the program and if i open the file, then i find the processid in that file.
Can you help me to solve this issue?