how can a running class get it's absolute path!

[a smoke]

And can you give me a way to get OS environment variable.thanks.

[Rene Larsen]

One way is this:

import java.net.*;
public class Test {
   public static void main(String[] args) {
      URL path = Test.class.getClassLoader().getResource("");
      System.out.println((path.toString()).substring(6) + Test.class.getName());
   }
}

/Rene
[ July 17, 2002: Message edited by: Rene Larsen ]

[Rene Larsen]

Here are two samples to get OS environment variable.

System.out.println(System.getProperty("java.home"));

To see witch properties you can get try this link:
http://java.sun.com/j2se/1.3/docs/api/java/lang/System.html
another way is:

try {
   Process p = Runtime.getRuntime().exec("cmd /c set JAVA_HOME");
   InputStreamReader isr = new InputStreamReader(p.getInputStream());
   BufferedReader br = new BufferedReader(isr);
   String myJavaHome = null;
   String s = null;
   while ((s = br.readLine()) != null) {
      myJavaHome = s;
   }
   br.close();
   isr.close();
   System.out.println(myJavaHome);
}
catch (IOException e) {
   /* do something */
}

/Rene

[Dave Vick]

a smoke
Welcome to the Java Ranch, we hope you�ll enjoy visiting as a regular however,
your name is not in keeping with our naming policy here at the ranch. Please change your display name to an appropriate name as shown in the policy.
Thanks again and we hope to see you around the ranch!!

[Frank Carver]

Rene Larsen wrote: [I]

import java.net.*;
public class Test {
   public static void main(String[] args) 
   {
      URL path = Test.class.getClassLoader().getResource("");
      System.out.println((path.toString()).substring(6) + Test.class.getName());   
   }
}

[/I]
Note that this will throw a NullPointerException (because "path" is null) if the class was loaded from a jar. It probably won't make much sense if the class was loaded over the network.
In general, expecting getResource() to only refer to real files on the local filesystem is a dangerous asumption.