J-Spring
Bi-annual Java conference organized by the NL-JUG. This is an all-day conference with lots of presentations in six different tracks:

• Core - topics on core Java APIs of Java SE
• Enterprise - topics on Java EE APIs, including web development, architecture, integration, and SOA/BPM related topics
• Methodology - topics concerning the software development process of Java projects
• Mobile & Embedded - Java on mobile devices, embedded or real-time usage
• New & Cool - popular new Java technology and/or remarkable application of Java technology in the real world
• Tools - supporting tools for designing and/or development of Java applications or automating the software development process