A big thank you to all the Contributors that made this release possible!

XChange is a Java library providing a unified API to all the major Bitcoin exchanges including: 

• MtGox - polling and streaming market data, trading and account data
• VirtEx - polling market data
• BTC-E - polling market data, trading and account data
• Bitstamp - polling market data, trading and account data
• CampBX - polling market data, trading and account data
• Bitcurex - polling market data
• BTC-China - polling market data, trading and account data
• Kraken - polling market data, trading and account data
• BitcoinCharts - polling market data (Bitcoin Exchange Rates)
• OpenExchangeRates - polling market data (Fiat Currency Exchange Rates)
• Blockchain Info - polling market data (Bitcoin Address Information)

Some more links: 

* 1.9.0 Release Blog Article - http://blog.xeiam.com/2013/10/xchange-190-released.html
* Change Log and Jars - http://xeiam.com/xchange_changelog.jsp
* Example Code - http://xeiam.com/xchange_examplecode.jsp

All exchanges in XChange also have a placeLimitOrderMethod.

If you have any land or a house for sale in Oberbayern, I'd be interested.

Highlights of this release are MtGox streaming, dependencies on ResCU and Java-Websockets, and many bugfixes. Bitcoin-24, Bitfloor, and BitcoinCentral were dropped as well.

Official Announcement is here.

Change Log is here.

Many thanks to the new contributors who helped make this release possible!

XChange is an open-source financial exchange library for Java.

Version 1.5.0 was released today. Mainly, we added three more exchanges: Bitcoin-24, BitcoinCentral, and Bitfloor.

Thanks to everyone who contributed code and worked on other issues!  

The current list of supported exchanges:

• Bitcoin24 - polling market, trades, and account data
• BitconCentral - polling market, trades, and account data
• Bitfloor - polling market data
• MtGox - polling and streaming market data, authenticated trading
• Bitstamp - polling market data, authenticated trading
• BTC-E - polling market data, authenticated trading
• VirtEx - polling market data
• CampBX - polling market, trades, and account data
• BitcoinCharts - polling market data (Bitcoin Exchange Rates)
• OpenExchangeRates - polling market data (Fiat Currency Exchange Rates)

Announcement
http://blog.xeiam.com/2013/03/xchange-150-released.html

Change Log
http://xeiam.com/xchange_changelog.jsp

Open Source Code (MIT license)
https://github.com/timmolter/XChange

Wiki on GitHub
https://github.com/timmolter/XChange/wiki

Artifacts on Maven Central
http://search.maven.org/#search%7Cga%7C1%7Cxeiam%20xchange

Feedback is appreciated!!
https://github.com/timmolter/XChange/issues

I love the new layout. And I especially like seeing Multibit first on the client list. I remember first trying the "default" client only to get very frustrated, but when I later tried out MultiBit it was smooth sailing.

That's insane!

Version 1.4.0 was released today. It is mostly a bugfix release.

Thanks to everyone who reported bugs, fixed, and tested code! 

Change Log
http://xeiam.com/xchange_changelog.jsp

Open Source Code (MIT license)
https://github.com/timmolter/XChange

Wiki on GitHub
https://github.com/timmolter/XChange/wiki

Artifacts on Maven Central
http://search.maven.org/#search%7Cga%7C1%7Cxeiam%20xchange

Feedback is appreciated!!
https://github.com/timmolter/XChange/issues

Looks great, Jim.

Hi Freemoney,

I think you're right. The next logical step would be to create an app, where one could buy and sell Bitcoin (and eventually other forex, stocks, futures, etc.) from several different exchanges. The GUI would give you an overview of all your accounts and quick access to place orders, transfer funds, etc.

If someone is planning on doing this in a Java desktop app or Android app, using XChange would give them a huge base to work off of.

Cheers, Tim

Here's some example code from the xchange-examples jar to demonstrate using the api key and requesting the data from OpenExchangeRates:

...and the result...

Hi Jim,

You can call getRefreshRate() on any exchange that implements CachedDataSession, such as OpenExchangeRates exchange, and it will give you the time in seconds representing the refresh rate for that particular data provider. CachedDataSessions cache the data internally as well, and make sure to only call out for new data at an appropriate interval. Another example of this is bitcoincharts. The refresh rate for that one is 15 minutes.

I hope that helps!

Yes, each user needs an authentication code which they can get for free by signing up at OpenExchangeRates (https://openexchangerates.org/). The free version limits you to 1000 requests per month I believe.

Our Financial Exchange Library for Java, XChange, has seen a lot of active development since the previous release in October 2012. We went from 2 to 7 exchange implementations thanks mostly to the growing community starting to support the project more.

Following is a list of the supported exchanges. More detailed info can be found here: https://github.com/timmolter/XChange/wiki/Exchange-Support, which includes planned future exchange implementations.

• MtGox - polling and streaming market data, authenticated trading
• Bitstamp - polling market data, authenticated trading
• BTC-E - polling market data, authenticated trading
• VirtEx - polling market data
• CampBX - polling market data
• BitcoinCharts - polling market data (Bitcoin Exchange Rates)
• OpenExchangeRates - polling market data (Fiat Currency Exchange Rates)

In this release, we introduced a new and improved REST interface that sits between our exchange classes and the class responsible for fetching JSON. It also gives XChange clients access to the raw unmarshalled JSON data if they want it, which was something XChange needed for a long time.

All exchange implementations have full-coverage unit tests.

We've been able to reduce the number of dependencies a lot. One of the main focuses of XChange is to be very lightweight. Most notably is the outdated org.json jar. We dug into the Socket.io code, and painstakingly swapped out the old code with our already-used Jackson JSON code. This is good news for apps like Bitcoinium and Multibit, which both use XChange, for keeping their executable footprint small.

Another major accomplishment with this release, is that the artifacts are now hosted on Maven Central.

We're thinking about adding an arbitrage API within XChange next as the MtGox, BTC-E, and Bitstamp implementations all contain trading functionality.

Open Source Code (MIT license)
https://github.com/timmolter/XChange

Wiki on GitHub
https://github.com/timmolter/XChange/wiki

Project Home
http://xeiam.com/xchange.jsp

Artifacts on Maven Central
http://search.maven.org/#search%7Cga%7C1%7Cxeiam%20xchange

Feedback is appreciated!!
https://github.com/timmolter/XChange/issues

Hi,

I'd be happy to do the Exchange Bot, if no one else claimed it yet, or if whoever is attempting it fails. I'm the lead dev of the XChange OSS project: https://github.com/timmolter/XChange

Cheers, Tim

Wir haben ein Open Source Java Library der XChange heisst: https://github.com/timmolter/XChange

Derzeit gibt es implementationen für:
MtGox
Bitstamp
BTC-E
CampBX
CaVirtex
OpenExchangeRates
und
BitcoinCharts.

Cheers, Tim

That's just crazy...

Hi Jim! How did you ever find this post?

Hi,

Could you please add me to the whitelist. I've been a part of the open source bitcoin comminity since late 2011. I'm the lead dev at XChange: https://github.com/timmolter/XChange

I've blogged about bitcoin as well: http://obscuredclarity.blogspot.de/search?q=bitcoin

Thanks a ton!

I trade on Mt.Gox, but never leave a balance there, neither in $ nor BTC.