public void getExchangeInfo(Exchange.Type currency, long quantity, Callback<Exchange> callback) throws GuildWars2Exception, NullPointerException {
		isValueValid(quantity);
		gw2API.getExchangeInfo(currency.name(), Long.toString(quantity)).enqueue(callback);
	}
public void getExchangeInfo ( Exchange . Type currency , long quantity , Callback < Exchange > callback ) throws GuildWars2Exception , NullPointerException { isValueValid ( quantity ) ; gw2API . getExchangeInfo ( currency . name ( ) , Long . toString ( quantity ) ) . enqueue ( callback ) ; }
For more info on exchange coins API go <a href="https://wiki.guildwars2.com/wiki/API:2/commerce/exchange/coins">here</a><br/>
Give user the access to {@link Callback#onResponse(Call, Response)} and {@link Callback#onFailure(Call, Throwable)} methods for custom interactions

@param currency exchange currency type
@param quantity The amount to exchange
@param callback callback that is going to be used for {@link Call#enqueue(Callback)}
@throws GuildWars2Exception  invalid value
@throws NullPointerException if given {@link Callback} is empty
@see Exchange Exchange info