The only thing remotely inforceable is caller class checking. You cannot
bypass an exception with setAccesible. Oracle went and removed
Reflection.getCallerClass() completely in favour of StackWalker. At least
we can share the SecurityManage ClassContext, SecurityActions seems the
appropriate venue for our stack trace peek to support the older versions
Java 7 and 8 does support method handles so we can cater for them. When doing
repeated invokes to the same method, keeping a reference to the Method handle
is much faster than reflection. Also the API is cleaner not having to Object[]
args etc. Worth the effort...
The main advantage is that we can do the privileged setAccessible during creation and
then freely invoke via the authorized method handle.
As per the javadocs:
Access checks are applied in the factory methods of Lookup, when a method handle is created.
his is a key difference from the Core Reflection API, since java.lang.reflect.Method.invoke
performs access checking against every caller, on every call.
The performance boost is just a bonus.
Oracle (or maybe it was still Sun) warns that we should prevent from exposing access we gain to
privileged functionality like the unsafe etc. Before Oracle decides to restrict us even more lets
make an effort at least.
With the unit tests warnings were squashed by suppressing them with SuppressWarnings annotations, instead of
reparing the issues as was done with the source. Reasons being...
* The tests might be relying on the types as they were defined.
* If the tests were written to test against the correct forms they would've/should've stipulated those.
* Even unused members might be important to tests so we attempt to change as little as possible.
The following were applied during multiple itterations through the source.
* Parameterize raw types.
* Mark unused members.
* Annotate override and deprecated methods.
* Convert loops to enhance for loop.
* Remove redundant else statements.
* Widening collection type references.
* Optimize code for improved readability.
* Squash compiler warnings.
* Identify smells.
There were minimal changes:
Some tests had their own runners these were discontinued as IDEs/maven run the tests anyway.
Removed the main methods for these.
2 tests were dependent on the running order so added the test sorter.
All tests succeed on junit 4 with legacy support.
A fix for older JDK8 versions: https://bugs.openjdk.java.net/browse/JDK-8041920
This caused random failures a little time after startup. Reported now so that when we upgrade javassist for JDK9 then we would not have to fork this class.
Due to the specification change of jigsaw, ClassLoader#defineClass()
cannot be invoked through reflection API. As a workaround,
--add-opens java.base/java.lang=ALL-UNNAMED
must be given to the JVM. The ant target "runtest9" adds this jvm
argument.
nickl-
Christian Melchior
Shigeru Chiba
chibash
Scott Marlow
Andres Luuk