(long tweet) Glassfish / Unsupported major.minor version 51.0
Case
On launching Glassfish 4 under Windows, I got the following error:
asadmin.bat start-domain Exception in thread "main" java.lang.UnsupportedClassVersionError: org/glassfish/admin/cli/AsadminMain : Unsupported major.minor version 51.0
Quickfix
Glassfish 4 is JEE6-compatible, therefore run Glassfish 4 with JRE 7 instead of JRE 6.
As a reminder, here is the list of majors/minor versions:
J2SE 8 = 52, J2SE 7 = 51, J2SE 6.0 = 50, J2SE 5.0 = 49, JDK 1.4 = 48, JDK 1.3 = 47, JDK 1.2 = 46, JDK 1.1 = 45