Problem wiht Running Batch File using Runtime.exec()

Question

I am writting one program which will create a jar file using a windows Batch file.
The main program is in the folder "d:\CmdExec.java".
The other one to which a jar file to be created is in the folder "e:\folder\HelloWorld.class"
The contents inside the "e:\folder" are
e:\folder\HelloWorld.class
e:\folder\mainClass.txt
e:\folder\run.bat
The mainClass.txt contains "Main-Class: HelloWorld"
The Run.bat file contains "jar cmf mainClass.txt HelloWorld.jar *.class"
The coding for CmdExec.java is as follows
import java.io.*;
import java.awt.Desktop;
public class CmdExec {
public static void main(String argv[]) {
try {
Desktop desktop = null;
if (Desktop.isDesktopSupported()) {
desktop = Desktop.getDesktop();
desktop.open(new File("e:\\folder\\run.bat"));
catch (Exception err) {
err.printStackTrace();
When i double click the file e:\folder\Run.bat, it will create a jar file for HelloWorld.class.
But, i want to create that jar file using the java program CmdExec.java.
When i run CmdExec.java, the batch file is opened. But it shows error as "Can't find the specified file"
But when i copy the following files to "d:\",
e:\folder\HelloWorld.class
e:\folder\mainClass.txt
the jar file is created using the CmdExec.java.
But,
e:\folder\HelloWorld.class
e:\folder\mainClass.txt
these files should be in the folder"e:\folder" only.
Can anyone Help me this Problem?
Or Anyother way for creating a jar file for one program by using another program?
Help me soon.............

Answer 1

Try this. It's not running a bat file. You can say it almost is a bat file.
import java.io.*;
import java.util.Scanner;
public class CmdExec {
    public static void main(String argv[]) {
        try {
            Process p = Runtime.getRuntime().exec("jar cmf mainClass.txt HelloWorld.jar *.class");
            Scanner s1=new Scanner(new InputStreamReader(p.getInputStream()));
            while(s1.hasNextLine())
                System.out.println(s1.nextLine());
            p.waitFor();
            System.out.println(p.exitValue());
            if(p.exitValue()==0)
                System.out.println("Okay");
            else
                System.out.println("Error");
        catch (Exception ex) {
            ex.printStackTrace();
}Run it in the same folder as mainClass.txt
Edited by: ColacX on Aug 1, 2008 10:35 AM