@Override
 public <V> V accept(final FixedIncomeInstrumentDefinitionVisitor<?, V> visitor) {
   return visitor.visitSwaptionCashFixedIborDefinition(this);
 }
 @Override
 public <U, V> V accept(final FixedIncomeInstrumentDefinitionVisitor<U, V> visitor, final U data) {
   return visitor.visitSwaptionCashFixedIborDefinition(this, data);
 }