JavaOne is an annual conference (since 1996) put on by Sun Microsystems to discuss Java technologies, primarily among Java developers. JavaOne is held at the Moscone Center in San Francisco, California usually between April and June and typically runs from Sunday to Friday. Technical sessions on a variety of topics are held during the day. In the evening, Birds of a Feather (BOF) sessions are held at the Moscone Center and surrounding hotels. BOF sessions allow people to focus in on a particular aspect of Java technology.

Access to the technical sessions, keynote presentations, exhibits and BOF sessions requires a conference pass which usually costs between $1795 to $1995 USD.
In 1999, the JavaOne conference played host to an event called the Hackathon, this event was a challenge set by John Gage. Attendees were to write a program in Java for the new Palm V using the infrared port to communicate with other Palm users and register it on the Internet.
CommunityOne
In 2007, an associated one-day event, CommunityOne, was initiated, for the broader free and open-source developer community. In 2008, the second annual CommunityOne event was held on May 5.
In 2009, CommunityOne expanded to New York City (CommunityOne East, March 18-19, 2009) and to Oslo, Norway (CommunityOne North). The third annual CommunityOne in San Francisco (now called CommunityOne North), will take place from June 1-3, 2009, at The Moscone Center.
In 2009, CommunityOne focuses on open-source innovation and implementation.
Tracks include:
- Cloud Platforms – Development and deployment in the cloud. - Social and Collaborative Platforms – Social networks and Web 2.0 trends. - RIAs and Scripting – Rich Internet Applications, scripting and tools. - Web Platforms – Dynamic languages, databases, and Web servers. - Server-side Platforms – SOA, tools, application servers, and databases. - Mobile Development – Mobile platforms, devices, tools and application development. - Operating Systems and Infrastructure – Performance, virtualization, and native development. - Free and Open – Open-source projects, business models, and trends.
The main conference on Monday, June 1, is free. Deep Dive technology tutorials on June 2 and June.
Show device
Each year at the conference there is a hardware device highlighted, available to attendees, typically before sold to the general public or at a steep discount.