If you have been doing development with Exchange Web Services (EWS) and develop with Java there has been an API which could be used called the EWS Java API.  In the past I've been asked about how often it got updated and if it might get made open source.  The answers we could provide were to check the APIs site where it was located and check for updates and ask questions there. It is also and API that's not updated very often - ie once in a blue moon.   So, to move this API forward some things had to change - see below:

The EWS Java API is an open source project on GitHub that can be updated and extended by the community. It is stylistically similar to the EWS Managed API and uses EWS SOAP requests and responses over the wire. Although you can't access all EWS SOAP operations by using the EWS Java API, with the recent creation of the open source project, we are looking to the community to bridge this gap. Note that Microsoft Support, with an appropriate support contract, will address any questions related to the EWS SOAP protocol but not the EWS Java API itself. The EWS Java API is available for download and community contribution on GitHub.

So, if you have made adaptions to this API and want to increase its capabilities then please do join in and congtribute to it.  If you have found issues then also please file bugs against it through GitHub.   Note that there are other products listed in GitHub, so be sure to pick the correct one as noted in the link below.

ews-java-api
https://github.com/OfficeDev/ews-java-api

 Here is the announcement:

Open sourcing Exchange Web Services (EWS) Java API
http://blogs.office.com/2014/08/28/open-sourcing-exchange-web-services-ews-java-api/

Note that this API is not eligible for developer support through a support case from the Java code perspective.  We do however provide developer support from the EWS protocol perspective (ie the over the wire traffic) when any language or API is used. 

If you haven't been noticing, a lot of things have been changing at MS.  New APIs, expanding into new platforms, new ways of doing things, faster paces...