[thredds] Upgrading to Java 7

We will start requiring Java 7 starting with CDM and TDS versions 4.4, later this year.

Meanwhile, we recommend that you start to make migration plans to Java 7 now. All supported version of CDM/TDS should work correctly with Java 7.

from Oracle:

"After November 2012, Oracle will no longer post updates of Java SE 6 to its public download sites. Existing Java SE 6 downloads already posted as of November 2012 will remain accessible in the Java Archive on Oracle Technology Network. Developers and end-users are encouraged to update to more recent Java SE versions that remain available for public download.

"As we always stated that an outdated installation can be a bad idea. For this reason, starting with 7u5 we will start to automatically upgrade Java installations on Microsoft Windows to Java SE 7. Initially a fraction of the installations will be automatically upgraded. After a while the automated update path will lead to Java SE 7 for all users by default.

"In addition, the default version available for download from Java.com will also change from Java SE 6 to Java SE 7 in the coming weeks.

"Please see this FAQ (http://java.com/java7faq/) for any questions. More details on Oracle’s Java SE Roadmap and EOL policy can be found at http://www.oracle.com/technetwork/java/javase/eol-135779.html .

"Moreover, I would like to use this opportunity to let you know that, in line with no longer posting updates of Java SE 6 after November 2012 to Oracle’s public download sites, we don’t have plans to contribute further changes to OpenJDK 6 after November 2012. Users of OpenJDK 6 should consider upgrading to OpenJDK 7, or, of course, to Oracle JDK 7, depending on their requirements."