For now, only the "pattern matching for switch" tests from previews 1
and 2 were adjusted to work in preview 3, because guarded patterns were
replaced by 'when' clauses in 'switch' blocks. Therefore, existing test
classes did not compile anymore and had to be replaced by syntactically
upgraded versions with content merged from preview 1 and 2 classes.

Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>

Relates to #170. Fixes the "Unknown constant type 17" problem.

Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>

- JDT Core dependency in pom.xml
- Constants.java
- LangUtil.java
- AjcTask.java
- messages_aspectj.properties

- XMLBasedAjcTestCaseForJava17Only.java
- XMLBasedAjcTestCaseForJava18*.java
- tests/bugs199
- tests/features199

- JavaVersionCompatibility.md
- README-199.html

- GitHub CI build

Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>

Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>

- Test all features which were preview in 14+15 and are now final in 16,
  compiling them with language level 16.
- For Java 15 we only have sanity tests (and of course the Java <14
  tests), compiling Java 16 features to target 15 does not seem to work.
- Test remaining Java 16 preview feature (sealed classes).
- Instead of overriding runTest(String) in several base classes like
  XMLBasedAjcTestCaseForJava*Only or XMLBasedAjcTestCaseForJava*OrLater,
  we now override setUp() from JUnit's TestCase base class. This will
  run before runTest(String) and make the tests fail much faster, if a
  user tries to run them on the wrong VM.

Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>

Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>

Signed-off-by: Lars Grefer <eclipse@larsgrefer.de>

- update to more recent JDT to pickup Nestmates fix
- bcel updated for NestMembers/NestHost attributes
- testcases for nestmates

Can read/write MethodParameters attribute.
Can read/write type annotation attributes.

The ANT targets in build.xml will still enable transformation of the packaging from org.aspectj.apache to org.apache for diffing with a new BCEL version, should one ever appear.