code: public List<Transaction> getTPTransaction(String API, Transaction.Time time, Transaction.Type type) throws GuildWars2Exception {
  		isParamValid(new ParamChecker(ParamType.API, API));
  		if (time == null || type == null)
  			throw new GuildWars2Exception(ErrorCode.TransTime, "Transaction time/type cannot be empty");
  		try {
  			Response<List<Transaction>> response = gw2API.getTPTransaction(time.getValue(), type.getValue(), API).execute();
  			if (!response.isSuccessful()) throwError(response.code(), response.errorBody());
  			return response.body();
  		} catch (IOException e) {
  			throw new GuildWars2Exception(ErrorCode.Network, "Network Error: " + e.getMessage());
  		}
  	}
docs: For more info on Transaction API go <a href="https://wiki.guildwars2.com/wiki/API:2/commerce/transactions">here</a><br/>
  Get transaction info linked to given API key
  
  @param API  API key
  @param time current | History
  @param type buy | sell
  @return list of transaction base on the selection, if there is nothing, return empty list
  @throws GuildWars2Exception see {@link ErrorCode} for detail
  @see Transaction transaction info