<GeneralConfiguration>
<section1>
<key1>value1</key1>
</section1>
<section2>
<key name="x">value_for_x</key>
<key name="y" a1="10" a2 ="15">
<a3>16</a3>
<a4>17</a4>
</key>
</section2>
</GeneralConfiguration>

// get a class responsible for implementing IConfig
     IConfig cfg;
// reading a simple key
     cfg.getValue("/section1/key1") -> value1
// reading a key with reserved name attribute
     cfg.getValue("/section2/key/x") -> value_for_x
// reading a key with reserved name attribute and its 
// attribute/child nodes
     cfg.getValue("/section2/key/y/a1") -> 10
     cfg.getValue("/section2/key/y/a3") -> 16

//Let us define an interface
interface LoggingInterface
{
     public void logMessage(String message);
}
//Let's see how we can use this interface
public void myLoggingFunction( Object o)
{
     if (o is LoggingInterface)
     {
          LoggingInterface log = (LoggingInterface)o;
          log.message("test message");
     }
     else
     {
          // sorry not sure of the type of this object
          throw new Exception("Unexpected type");
     }
}

public class FileLogger : LoggingInterface
{
     private FileOutputStream fs = null;
     public FileLogger(string filename)
     {
          fs = new FileOutputstream(filename);
     }
     // implement the following method to complete the 
	 // contract required by LoggingInterface
     public void logMessage(String message)
     {
          fs.println(message);
     }
     public close()
     {
          fs.close();
     }
}

FileLogger     fileLogger = new FileLogger("myfile");
     myLoggingFunction(fileLogger);

public class EventLogger : ILog
{
     ... other code
     public void logMessage(string message)
     {
          ..  do the needful
     }
}

FileLogger  fileLogger = new FileLogger("myfile");
     myLoggingFunction(fileLogger);

EventLogger eventLogger = new EventLogger(..);
     myLoggingFunction(eventLogger);

LoggingInterface log = MyUtility.getLogger();
     myLoggingFunction(log);

public LoggingInterface getLogger()
     {
          return new FileLogger("myfile");
          // return new EventLogger();
     }

<request name="logger'>
          <classname>EventLogger
     </request>

public LoggingInterface getLogger()
     {
          IConfig cfg = ...
          string loggerClassname = cfg.getValue
("/request/logger/classname","EventLogger");
          Object o = instantiateAnObjectForItsClassname(
		      loggerClassName);
// code is not provided for this function
          LoggingInterface log = (LoggingInterface)o;
          return log;
     }

public static Object getObject(string interfacename)
     {
          IConfig cfg = ...
          string interfaceClassname = cfg.getValue("/request/" +
interfacename + "/classname");
          Object o = instantiateAnObjectForItsClassname(
		      loggerClassName);
// code is not provided for this function
          return o;
     }