Ontopia runs on Java 1.7 and higher versions. This means that all code in the project must compile under Java 1.7. Features and APIs from newer Java versions cannot be used until an official upgrade to a newer Java version is performed.

This may sound like an unnecessarily onerous restriction, but many corporate environments are very restrictive with the Java versions they run, basically because they need to do extensive testing on their environment before they will allow a certain Java version, and then roll out that version for their entire environment. This makes it necessary to be relatively conservative with the Java versions supported.

The mainline code does not yet use Java 7 features extensively. This means that you can still compile and use Ontopia in a Java 6 environment. The only exception to this is the ontopia-jdbcspy module. There is an older copy of this code available in the sandbox for use with Java 6.

Java 5 is no longer supported by Ontopia.

However, our general policy is the following:

• All code in /ontopia in Subversion (but not necessarily in TheSandbox) must compile with 1.7.
• All official releases must be built with Java 1.7.
• Anyone can build the code with any Java version they wish, if they can.
• Patches to make the code build with another Java version are accepted so long as they do not break compilation on 1.7 (and do not distort the code too much).