import java.util.*;
/********************************************************
 * Get all System environment variables name/value pairs
*********************************************************/

public class SystemEnv
{
    public static void main(String[] args)
    {
        Map env = System.getenv();                              //get all the system environement variables

        Set keys = env.keySet();                                //get all the env variable keys into a Set

        Iterator iterator = keys.iterator();                    //create an iterator for the keys

        System.out.printf("%-30s %s \n", " ENVIRONMENT ", " ENVIRONMENT  ");
        System.out.printf("%-30s %s \n", "VARIABLE NAME", "VARIABLE VALUE");
        System.out.printf("%-30s %s \n", "-------------", "--------------");
    
        while (iterator.hasNext())
        {
            String varName  = (String) iterator.next();

            String varValue = (String) env.get(varName);

            System.out.printf("%-30s %s \n", varName, varValue);
        }
    }
}