The Oracle Java Update tool on my Windows PC is pretty insistent that it wants to update my machine to Java 7u7 and REMOVE Java 6. Is it safe to use Java 7u7 for both Lucene Solr development and running Solr yet? My presumption has been that Lucene/Solr still “requires” Java 6.
The 4.0 Solr README.txt says to use the Java 6 JDK, but then adds “verify that the Java version is 1.6 or later ”, implying that a later release would be okay. Given that Java 7 will be the “current” release, the README should make some specific statement regarding Java 7. And maybe the top-level README.txt should have a Java version statement – unless both 7 and 6 are fine – although there is a minimum update level that works for 7 and Lucene, right? In any case, clear guidance should be provided. The Solr 4.0 CHANGES.txt does say “You need a Java 1.6 VM or later installed”, suggesting that Java 7 is fine. No mention of Java version requirement in the Lucene CHANGES.txt. I may just manually install 7u7 and not use it to avoid the update notice until Lucene/Solr “upgrades” to Java 7, but I suspect a fair number of people will simply take the update and say goodbye to Java 6. -- Jack Krupansky
