Add support for compilation on Java 10.

[rgrunber]

• Fixes #55
• Change javah to javac in ant task
• Add @Native annotation to static fields
• Set source/target to 1.8 for maven-compiler-plugin as 1.6 not supported
• Remove redundant definition from maven-compiler-plugin

Signed-off-by: Roland Grunberg rgrunber@redhat.com

[rgrunber]

We had to do very similar work in Fedora to get things building on Java 11, so this is just upstreaming some of those changes.

The build fails due to nativeheaderdir not being recognized by ant ( Apache Ant(TM) version 1.9.6 compiled on July 20 2018 ) . I think at least 1.9.8 is needed to use this attribute. ( https://ant.apache.org/manual/Tasks/javac.html )

[headius]

I am looking at these changes today, sorry they got left behind over the summer!

[headius]

Thank you for the changes!

We had been planning these changes so I don't see any big issue incorporating them. We will debate the impact of dropping support for Java 6 and 7 and try to get this merged in shortly.

[headius]

Looks like the ant on Travis is too old to have the new nativeheaderdir option for javac. Shouldn't stop merging though; I'll try to update it on master.

[headius]

Ant is updated on master, we'll proceed with this and sort out remaining issues there.

[headius]

I fixed a few more references to 1.6 on master (and a couple to Java 5), fixed version parsing in Platform, and got Java 8 and Java 11 running CI tests on Github. Will be pushing out a 1.3 release with this after some discussion about module support.

[headius]

The 1.3 release will also have a module for the first time: org.jnrproject.jffi.