Package org.knowm.xchange.simulated

Class SimulatedExchange

java.lang.Object

org.knowm.xchange.BaseExchange

org.knowm.xchange.simulated.SimulatedExchange

All Implemented Interfaces:

Exchange

public class SimulatedExchange
extends BaseExchange

A simple, in-memory implementation which mocks out the main elements of the XChange generic API in a consistent way. The effect is to create a virtual "exchange" that you can connect to from multiple threads and simulate a real exchange. Intended for integration testing of higher order components.

This is not remotely suitable for use as a real-world exchange. The concurrency is extremely coarse-grained and most data transforms involve data mutation with no . If any errors occur midway through a trade, they are likely to leave the system in an inconsistent state. And nothing gets saved to a database anyway.

If you start using this for running a real exchange, you will suffer a stolen.

Author:

Graham Crockford

Field Summary

Fields

Modifier and Type	Field	Description
static final String	ACCOUNT_FACTORY_PARAM	As with ENGINE_FACTORY_PARAM, provides a default unshared but optionally shared instance of AccountFactory.
static final String	ENGINE_FACTORY_PARAM	Allows the scope of the simulated exchange to be controlled.
static final String	ON_OPERATION_PARAM	Provides a SimulatedExchangeOperationListener.

Fields inherited from class org.knowm.xchange.BaseExchange

accountService, exchangeMetaData, exchangeSpecification, logger, marketDataService, tradeService

Fields inherited from interface org.knowm.xchange.Exchange

USE_SANDBOX

Constructor Summary

Constructors

Constructor	Description
SimulatedExchange()

Method Summary

Modifier and Type	Method	Description
SimulatedAccountService	getAccountService()	An account service typically provides access to the user's private exchange data
ExchangeSpecification	getDefaultExchangeSpecification()
SimulatedMarketDataService	getMarketDataService()	A market data service typically consists of a regularly updated list of the available prices for the various symbols
si.mazi.rescu.SynchronizedValueFactory<Long>	getNonceFactory()	The nonce factory used to create a nonce value.
SimulatedTradeService	getTradeService()	An trade service typically provides access to trading functionality
protected void	initServices()
void	remoteInit()	Initialize this instance with the remote meta data.

Methods inherited from class org.knowm.xchange.BaseExchange

applySpecification, getExchangeInstruments, getExchangeMetaData, getExchangeSpecification, getMetaDataFileName, loadExchangeMetaData, loadMetaData, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.knowm.xchange.Exchange

getResilienceRegistries

Field Details

ENGINE_FACTORY_PARAM

public static final String ENGINE_FACTORY_PARAM

Allows the scope of the simulated exchange to be controlled. Pass to ExchangeSpecification.setExchangeSpecificParametersItem(String, Object) to choose one of:

• new MatchingEngineFactory() - default. Each instance of SimulatedExchange works on a different virtual exchange with its own set of order books, thus the simulated exchange is single-user. Recommended for unit testing.
• An existing, shared instance of MatchingEngineFactory - Create your own factory and share it between SimulatedExchange instances to allow those specific instances to share the same order books and thus trade against each other. Recommended for integration testing.

See Also:

• Constant Field Values

ACCOUNT_FACTORY_PARAM

public static final String ACCOUNT_FACTORY_PARAM

As with ENGINE_FACTORY_PARAM, provides a default unshared but optionally shared instance of AccountFactory.

See Also:

• Constant Field Values

ON_OPERATION_PARAM

public static final String ON_OPERATION_PARAM

Provides a SimulatedExchangeOperationListener.

See Also:

• Constant Field Values

Constructor Details

SimulatedExchange

public SimulatedExchange()

Method Details

getNonceFactory

public si.mazi.rescu.SynchronizedValueFactory<Long> getNonceFactory()

Description copied from interface: Exchange

The nonce factory used to create a nonce value. Allows services to accept a placeholder that is replaced with generated value just before message is serialized and sent. If a method of a rest accepts ValueFactory as a parameter, it's evaluated, the message is serialized and sent in a single synchronized block.

Specified by:

getNonceFactory in interface Exchange

Overrides:

getNonceFactory in class BaseExchange

Returns:

Synchronized value factory

getDefaultExchangeSpecification

public ExchangeSpecification getDefaultExchangeSpecification()

Returns:

A default ExchangeSpecification to use during the creation process if one is not supplied

initServices

protected void initServices()

Specified by:

initServices in class BaseExchange

remoteInit

public void remoteInit()
                throws IOException,
ExchangeException

Description copied from interface: Exchange

Initialize this instance with the remote meta data. Most exchanges require this method to be called before Exchange.getExchangeMetaData(). Some exchanges require it before using some of their services.

Specified by:

remoteInit in interface Exchange

Overrides:

remoteInit in class BaseExchange

Throws:

IOException

ExchangeException

getMarketDataService

public SimulatedMarketDataService getMarketDataService()

Description copied from interface: Exchange

A market data service typically consists of a regularly updated list of the available prices for the various symbols

This is the non-streaming (blocking) version of the service

Specified by:

getMarketDataService in interface Exchange

Overrides:

getMarketDataService in class BaseExchange

Returns:

The exchange's market data service

getAccountService

public SimulatedAccountService getAccountService()

Description copied from interface: Exchange

An account service typically provides access to the user's private exchange data

Typically access is restricted by a secret API key and/or username password authentication which are usually provided in the ExchangeSpecification

Specified by:

getAccountService in interface Exchange

Overrides:

getAccountService in class BaseExchange

Returns:

The exchange's account service

getTradeService

public SimulatedTradeService getTradeService()

Description copied from interface: Exchange

An trade service typically provides access to trading functionality

Typically access is restricted by a secret API key and/or username password authentication which are usually provided in the ExchangeSpecification

Specified by:

getTradeService in interface Exchange

Overrides:

getTradeService in class BaseExchange

Returns:

The exchange's trade service