Runtim exec() method not working.....giving Exception

Question

whts the code to use exec() method. i m using it as follows and also catching exception.
Runtime r=Runtime.getRuntime();
Process p=r.exec("java A");
code is giving IOException at runtime with error=2.

Answer 1

Here is an example I used when I first needed to test the runtime.exec
import java.util.*;
import java.lang.*;
import java.io.*;
public class TestRuntime {
    public static void main(String args[])
        try
            Runtime rt = Runtime.getRuntime();
            Process proc = rt.exec("java A");
            InputStream stderr = proc.getErrorStream();
            InputStreamReader isr = new InputStreamReader(stderr);
            BufferedReader br = new BufferedReader(isr);
            String line = null;
            System.out.println("<ERROR>");
            while ( (line = br.readLine()) != null)
                System.out.println(line);
            System.out.println("</ERROR>");
            int exitVal = proc.waitFor();
            System.out.println("Process exitValue: " + exitVal);
        } catch (Throwable t)
            t.printStackTrace();
}Are you waiting for the process to end before exiting your program?