I m enable to run Linux command by Java code,

[Mohit Mehral]

Hi programmer's,
i have made javaCode, program run perfectly but created file not having
any data.i need a code which run perfectly and also save output of
command in textfile.Please provide exect matiral,plz dnt send the link.
Let me describe in brife:
I need to play command " df -h > text.txt"
below program create a file but never add data in text.txt
i havent modifyed it for linux(red hat 9).
*************************
// GoodWinRedirect.java
import java.util.*;
import java.io.*;

class StreamGobbler extends Thread
{
InputStream is;
String type;
OutputStream os;

StreamGobbler(InputStream is, String type)
{
this(is, type, null);
}

StreamGobbler(InputStream is, String type, OutputStream redirect)
{
this.is = is;
this.type = type;
this.os = redirect;
}

public void run()
{
try
{
PrintWriter pw = null;
if (os != null)
pw = new PrintWriter(os);

InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line=null;
while ( (line = br.readLine()) != null)
{
if (pw != null)
pw.println(line);
System.out.println(type + ">" + line);
}
if (pw != null)
pw.flush();
} catch (IOException ioe)
{
ioe.printStackTrace();
}
}
}

public class GoodWinRedirect
{
public static void main(String args[])
{
if (args.length < 1)
{
System.out.println("USAGE java GoodWinRedirect
<outputfile>");
System.exit(1);
}

try
{
FileOutputStream fos = new FileOutputStream(args[0]);
Runtime rt = Runtime.getRuntime();
Process proc = rt.exec("java jecho 'Hello World'");
// any error message?
StreamGobbler errorGobbler = new
StreamGobbler(proc.getErrorStream(), "ERROR");


// any output?
StreamGobbler outputGobbler = new
StreamGobbler(proc.getInputStream(), "OUTPUT", fos);

// kick them off
errorGobbler.start();
outputGobbler.start();

// any error???
int exitVal = proc.waitFor();
System.out.println("ExitValue: " + exitVal);
fos.flush();
fos.close();
} catch (Throwable t)
{
t.printStackTrace();
}
}
}

 

[Gordon Beaton]

i have made javaCode, program run perfectly but created file not
having any data.

In that case I'd say your program doesn't run perfectly.

You closed the FileOutputStream, but really you should be closing the
PrintWriter instead when you've finished writing to it.

/gordon