Accessing hostname for smtp mail server

Each and every unix system have differenet host names for this smtp mail server connections. And this code used to dynamically fetch the values.

public class demoClass {
 
 String Base;
 String Host;
 private void loadVariables() 
 {
  
  Base = System.getProperty("COMP_BASE");
  Host = System.getProperty("HOST_NAME");
  System.out.println(Base); 
  System.out.println(Host); 
 }
 

public static void main(String[] args){
 demoClass a = new demoClass();
 a.loadVariables();
}
}

export CLASSPATH=$CLASSPATH:./
export JAVA_HOME=/opt/java1.4/
export PATH=/opt/java1.4/jre/bin:$PATH
HOST_NAME=$(uname -n)
java -DASAP_BASE=$ASAP_BASE -DHOST_NAME=$HOST_NAME demoClass