code: public static double getDouble(String name, double defaultVal){
          if(getConfiguration().containsKey(name)){
              return getConfiguration().getDouble(name);
          } else {
              return defaultVal;
          }
      }
docs: Get the property object as double, or return defaultVal if property is not defined.
  
  @param name
  property name.
  @param defaultVal
  default property value.
  @return
  property value as double, return defaultVal if property is undefined.