}
public Buffer marshallExchange(CamelContext camelContext, Exchange exchange) throws IOException {
DataByteArrayOutputStream baos = new DataByteArrayOutputStream();
// use DefaultExchangeHolder to marshal to a serialized object
DefaultExchangeHolder pe = DefaultExchangeHolder.marshal(exchange, false);
// add the aggregated size property as the only property we want to retain
DefaultExchangeHolder.addProperty(pe, Exchange.AGGREGATED_SIZE, exchange.getProperty(Exchange.AGGREGATED_SIZE, Integer.class));
// add the aggregated completed by property to retain
DefaultExchangeHolder.addProperty(pe, Exchange.AGGREGATED_COMPLETED_BY, exchange.getProperty(Exchange.AGGREGATED_COMPLETED_BY, String.class));
// add the aggregated correlation key property to retain