Launching command containing pipe from Java

Hi,
i have some troubles to launch a command containing pipe from java.
I've tried to backslash the pipe but it still not work.
Maybe someone has an idea about that :
head -102050 /data/a_very_big_file | tail -5
the idea is to get 5 lines in the middle of a very big file.
To launch commands from java i use i think the classical way,
something like :
Process p = Runtime.getRuntime().exec(commande[0], this.envp, new File(this.pathExecution));
I obtain this error :
ERROR : head: invalid option -- 5
ERROR : Try `head --help' for more information.
Thanks for your help,
kevin.

kevleb wrote:
yes same result...
but i think the problem come from the fact
that when you pipe your result of a command,
you launch an other process (is that true).i don't know if another process is launched (the probability is rather high, though)
but even if that's the case, from the time you rely on a shell and not directly on exec(), i think it shouldn't be a problem to include a | inside the command ; i don't have an idea why it gives you that message error :\

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org.newio.utils.BrowserLauncher.openURL("your url here")dfwtc
package org.newio.utils;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.*;
public class BrowserLauncher
    private static int jvm;
    private static Object browser;
    private static boolean loadedWithoutErrors;
    private static Class mrjFileUtilsClass;
    private static Class mrjOSTypeClass;
    private static Class macOSErrorClass;
    private static Class aeDescClass;
    private static Constructor aeTargetConstructor;
    private static Constructor appleEventConstructor;
    private static Constructor aeDescConstructor;
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    private static Method getFileType;
    private static Method makeOSType;
    private static Method putParameter;
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    private static Object kSystemFolderType;
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    private static Integer kAutoGenerateReturnID;
    private static Integer kAnyTransactionID;
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    private static final int WINDOWS_9x = 3;
    private static final int OTHER = -1;
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    private static final String FINDER_CREATOR = "MACS";
    private static final String GURL_EVENT = "GURL";
    private static final String FIRST_WINDOWS_PARAMETER = "/c";
    private static final String SECOND_WINDOWS_PARAMETER = "start";
    private static final String NETSCAPE_OPEN_PARAMETER_START = " -remote 'openURL(";
    private static final String NETSCAPE_OPEN_PARAMETER_END = ")'";
    private static String errorMessage;
    private BrowserLauncher()
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        default:
            break;
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                Class osUtilsClass = Class.forName("com.apple.MacOS.OSUtils");
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                Class aeClass = Class.forName("com.apple.MacOS.ae");
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                aeTargetConstructor = aeTargetClass.getDeclaredConstructor(new Class[] {
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                appleEventConstructor = appleEventClass.getDeclaredConstructor(new Class[] {
                    Integer.TYPE, Integer.TYPE, aeTargetClass, Integer.TYPE, Integer.TYPE
                aeDescConstructor = aeDescClass.getDeclaredConstructor(new Class[] {
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                return false;
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                errorMessage = nsme.getMessage();
                return false;
            catch(NoSuchFieldException nsfe)
                errorMessage = nsfe.getMessage();
                return false;
            catch(IllegalAccessException iae)
                errorMessage = iae.getMessage();
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                mrjOSTypeClass = Class.forName("com.apple.mrj.MRJOSType");
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                kSystemFolderType = systemFolderField.get(null);
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                    mrjOSTypeClass
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                return false;
            catch(NoSuchMethodException nsme)
                errorMessage = nsme.getMessage();
                return false;
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                errorMessage = se.getMessage();
                return false;
            catch(IllegalAccessException iae)
                errorMessage = iae.getMessage();
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        return true;
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                Object aeTarget = aeTargetConstructor.newInstance(new Object[] {
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                Integer gurlType = (Integer)makeOSType.invoke(null, new Object[] {
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                errorMessage = iae.getMessage();
                return browser;
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                browser = null;
                errorMessage = ie.getMessage();
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                browser = null;
                errorMessage = ite.getMessage();
                return browser;
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            try
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                browser = null;
                errorMessage = iare.getMessage();
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            catch(IllegalAccessException iae)
                browser = null;
                errorMessage = iae.getMessage();
                return browser;
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                errorMessage = ite.getTargetException().getClass() + ": " + ite.getTargetException().getMessage();
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                try
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if(file.isFile())
Object fileType = getFileType.invoke(null, new Object[] {
file
if("FNDR".equals(fileType.toString()))
browser = file.toString();
return browser;
catch(IllegalArgumentException iare)
browser = browser;
errorMessage = iare.getMessage();
return null;
catch(IllegalAccessException iae)
browser = null;
errorMessage = iae.getMessage();
return browser;
catch(InvocationTargetException ite)
browser = null;
errorMessage = ite.getTargetException().getClass() + ": " + ite.getTargetException().getMessage();
return browser;
browser = null;
break;
case 2: // '\002'
browser = "cmd.exe";
break;
case 3: // '\003'
browser = "command.com";
break;
case -1:
default:
browser = "netscape";
break;
return browser;
public static void openURL(String url)
throws IOException
if(!loadedWithoutErrors)
throw new IOException("Exception in finding browser: " + errorMessage);
Object browser = locateBrowser();
if(browser == null)
throw new IOException("Unable to locate browser: " + errorMessage);
switch(jvm)
case 0: // '\0'
Object aeDesc = null;
try
try
aeDesc = aeDescConstructor.newInstance(new Object[] {
url
putParameter.invoke(browser, new Object[] {
keyDirectObject, aeDesc
sendNoReply.invoke(browser, new Object[0]);
catch(InvocationTargetException ite)
throw new IOException("InvocationTargetException while creating AEDesc: " + ite.getMessage());
catch(IllegalAccessException iae)
throw new IOException("IllegalAccessException while building AppleEvent: " + iae.getMessage());
catch(InstantiationException ie)
throw new IOException("InstantiationException while creating AEDesc: " + ie.getMessage());
break;
finally
aeDesc = null;
browser = null;
case 1: // '\001'
Runtime.getRuntime().exec(new String[] {
(String)browser, url
break;
case 2: // '\002'
case 3: // '\003'
Runtime.getRuntime().exec(new String[] {
(String)browser, "/c", "start", url
break;
case -1:
Process process = Runtime.getRuntime().exec((String)browser + " -remote 'openURL(" + url + ")'");
try
int exitCode = process.waitFor();
if(exitCode != 0)
Runtime.getRuntime().exec(new String[] {
(String)browser, url
catch(InterruptedException ie)
throw new IOException("InterruptedException while launching browser: " + ie.getMessage());
break;
default:
Runtime.getRuntime().exec(new String[] {
(String)browser, url
break;
static
loadedWithoutErrors = true;
String osName = System.getProperty("os.name");
if("Mac OS".equals(osName))
String mrjVersion = System.getProperty("mrj.version");
String majorMRJVersion = mrjVersion.substring(0, 3);
try
double version = Double.valueOf(majorMRJVersion).doubleValue();
if(version == 2D)
jvm = 0;
} else
if(version >= 2.1000000000000001D)
jvm = 1;
} else
loadedWithoutErrors = false;
errorMessage = "Unsupported MRJ version: " + version;
catch(NumberFormatException numberformatexception)
loadedWithoutErrors = false;
errorMessage = "Invalid MRJ version: " + mrjVersion;
} else
if(osName.startsWith("Windows"))
if(osName.indexOf("9") != -1)
jvm = 3;
} else
jvm = 2;
} else
jvm = -1;
if(loadedWithoutErrors)
loadedWithoutErrors = loadClasses();
suck my balls

Problem in executing Linux command from Java Programme.

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will anybody help me solve this problem.

It may be a Problem of Catching the Echoes back from the Processes...I have a Program which Captures the Echoes..see if it works
import java.beans.PropertyChangeEvent;import java.beans.PropertyChangeListener;import java.beans.PropertyChangeSupport;import java.lang.ref.WeakReference;/** * Implements a proxy property change listener using a weak reference to avoid memory locking that would occur if it * was a strong reference. To understand this, we hve to understand that the property change listeners themselves are * hilding onto panels and other objects with strong java references. If the panel goes away while we are viewing an * object, we have a circular emory hold situation where the panel cant be collected because it has ahold of the * property and the property cannot because it has ahold of the pane. If we use weak references instead, then the hard * link between the listener and the producer is softened to almost nothing. */public class WeakPropertyChangeListener implements PropertyChangeListener { /**   * A poperty change support object is included here so that the listener can remove   * himself from the listeners if the reference internally goes to null.   */ private PropertyChangeSupport pcs = null; /** Holds the weak reference to the real listener. */ private WeakReference weakRef = null; /**   * Constructs a new Proxy object for the given support and listener.   * @param pcs The property change support that this object will be using.   * @param pcl The real listener.   */ public WeakPropertyChangeListener(PropertyChangeSupport pcs, PropertyChangeListener pcl) {    if (pcs == null) throw new NullPointerException("pcs");    if (pcl == null) throw new NullPointerException("pcl");    this.pcs = pcs;    weakRef = new WeakReference(pcl); } /** @see <{PropertyChangeListener}> */ public void propertyChange(PropertyChangeEvent changeEvent) {    Object referrant = weakRef.get();    if (referrant == null) {      pcs.removePropertyChangeListener(this);    } else {      ((PropertyChangeListener)referrant).propertyChange(changeEvent);    } } /** Returns true for comparison to referrant or this. */ public boolean equals(Object obj) {    if (obj instanceof WeakPropertyChangeListener) return super.equals(obj);    else if (obj != null)return obj.equals(weakRef.get());    else return false; }}// snipet public void addPropertyChangeListener(PropertyChangeListener listener) {    this.propertyChangeSupport.addPropertyChangeListener(      new WeakPropertyChangeListener(this.propertyChangeSupport, listener)); } public void removePropertyChangeListener(PropertyChangeListener listener) {    this.propertyChangeSupport.removePropertyChangeListener(listener); }

Problem while running dos command from java program

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

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?

Launching command containing pipe from Java

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