RFR: 8259267: Refactor LoaderLeak shell test as java test. [v14]

[Igor Ignatyev]

On Wed, 3 Mar 2021 15:55:03 GMT, Ivan Šipka <isipka at openjdk.org> wrote:

>> Refactor `test/jdk/java/lang/annotation/loaderLeak/LoaderLeak.sh` as java test.
>
> Ivan Šipka has updated the pull request incrementally with one additional commit since the last revision:
> 
>   8166026: Refactor java/lang shell tests to java

test/jdk/java/lang/annotation/LoaderLeakTest.java line 74:

> 72:             catch (NullPointerException npe) {
> 73:                 throw new AssertionError("c.get() should never return null", npe);
> 74:             }

I don't think it's the right way to handle that, you don't know if this NPE is from `c.get`, so the exception messages might be misleading. I'd just remove try/catch, if NPE occurs jtreg will report the test as failed w/ NPE as a reason, so whoever analyzes it will be able to understand.

alternatively, you can save c.get into a local variable which you nulls later one, e.g.
 ```
static void doTest(boolean readAnn) throws Exception {
...
var tmp = c.get();
if (t == null) throw new AssertionError("c.get is null");
if (t.getClassLoader() != loader) throw new AssertionError("wrong classloader");
t = null;

-------------

PR: https://git.openjdk.java.net/jdk/pull/1577