I want to write a Swing application in Griffon
but I am not sure what versions of Java I can support.
According to the Griffon website, 1.5 or higher.
http://groovy.codehaus.org/Installing+Griffon (broken link)
[Update December 2024]
JDK 1.7 was the minimum required for Griffon 2.0 up until 2.14.0. Version 2.15.0 onwards requires Java 8.