Switch to Java 11

[p-bakker]

From @gbrail (see #972 (comment)):

This is a long long discussion, but I'm ready to say that Rhino can move beyond Java 8 after 1.7.14. Later Java versions are getting pretty ubiquitous, and the log4j thing helped push some people along.

I'd like to propose Java 11 as the new baseline going forward, with support for newer versions of course.

Does that make sense?

[p-bakker]

To me it does, but a couple of things I'm not sure about:

• What would that do to support for Rhino on Android?
• Is this in any way related to (the discussion about) Modular Java
• Assuming we'll have a v1.7.15 before a v2.0.0: should we switch to Java 11 for v1.7.15 or postpone that for v2.0.0?

[p-bakker]

We also have a case for switching to another Java version: #1075

[p-bakker]

And I have the idea these are also somewhat related to this topic:

• Switch to a multiproject/modular source layout
• Current VMBridge is not suitable for modular JDKs
• Remove RhinoSecurityManager and refactor relevant security-related due to pending deprecation and removal of the Java Security Manager

[gbrail]

I opened a PR that upgrades the build to require Java 11 minimum, and upgrades some tools so that they will work better with newer versions. If a few of you can take a look, I'm happy to merge that and then start removing some of the older support for older Java versions.

[gbrail]

Any more opinions on this? I am ready to merge that PR and at least start the process of moving to Java 11 as a minimum.

[p-bakker]

If nobody else objects, I suggest going for it

[gbrail]

#1344

[p-bakker]

Also see #1363

[p-bakker]

Discussion closed, as of today Rhino requires Java 11 or higher