This PR makes it possible to build the Nomulus code base using Java 17.
Building with Java 11 continue to be possible and the resulting bytecodes are
still at Java 8 level. Also upgraded Gradle to 8.5.
There are several necessary changes to make this happen:
1. Some Gradle plugins need to be upgraded to support Java 17, notably
errorprone. As a result, a lot more "errors" were caught and corrected.
2. All test code are now built and run at Java 8 level. Previously it was left
undefined (which defaults to the version of the compiler) and had led to
situations where we inadvertently called Java 8+ features in production that
are not caught by tests. The change also made the java8compatibility subproject
obsolete, which is therefore removed.
3. Removed the docs subproject. Its main use is to generate flows.md, but it
relies heavily on Java internal APIs that have changed significant with each
version. Upgrading to Java 11 required extensive refactoring of the code there,
and Java 17 again removed many APIs that were used. I don't think it is worth
the maintenance effort just to have a tool to generate flows.md which no one
actually reads.
4. Capped a few GCP dependencies because the latest version depends on
grpc-java >= 1.59.0, which includes a runtime incompatibility
(https://github.com/grpc/grpc-java/releases/tag/v1.59.0).
This includes removing (hopefully temporarily) the gradle-lint plugin as
it is incompatible with various Gradle versions (see
https://github.com/nebula-plugins/gradle-lint-plugin/issues/393). This
is somewhat unfortunate since the plugin is useful for removing unused
dependencies, though with the relatively small amount of Gradle code we
write hopefully it will not be missed much. If Nebula changes their
code to be compatible with Gradle 8+, we can re-add it easily.
This upgrade means we can remove the code added in 342051e1.
This is an 'easy' upgrade that requires a minor change in
common/build.gradle and the removal of an unnecessary import in buildSrc.
Gradle 7.4 and above has breaking changes that break the latest nebula lint plugin. We may have to wait a while.
* Convert to gradle 7.
* More fixes, regenerated lockfiles.
* Update lockfiles for dependency update.
* Fix show_upgrade_diff for new lockfile format
* Add property for allowInsecureProtocol
Allow us to override the restriction against use of plain HTTP for
communication to dependency repositories. We need this to be able to use a
local proxy for dependency gathering.
* Checking in missing gradle.lockfile
