private ExchangeRateManager(){
  if (System.getProperty("EXPERIMENTAL") == null)   throw new UnsupportedOperationException("Work in progress");
  addKnownRates();
}

private ExchangeRateManager ( ) { if ( System . getProperty ( "EXPERIMENTAL" ) == null ) throw new UnsupportedOperationException ( "Work in progress" ) ; addKnownRates ( ) ; }
constructs a new exchangeratemanager and initialises the most used rates . note : private ; should only be accessed by getinstance ( ) .
