import junit.framework.AssertionFailedError;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Base class for JSR166 Junit TCK tests. Defines some constants, utility methods and classes, as
 * well as a simple framework for helping to make sure that assertions failing in generated threads
 * cause the associated test that generated them to itself fail (which JUnit does not otherwise

 *  Fix: Throw `UnknownServiceException` if a cleartext connection is attempted
    when explicitly forbidden.
 *  Fix: Throw a `SSLPeerUnverifiedException` when host verification fails.
 *  Fix: MockWebServer explicitly closes sockets. (On some Android releases,
    closing the input stream and output stream of a socket is not sufficient.
 *  Fix: Buffer outgoing HTTP/2 frames to limit how many outgoing frames are
    created.

* `www_redirect` – Wenn auf True gesetzt, werden Requests an Nicht-www-Versionen der erlaubten Hosts zu deren www-Gegenstücken umgeleitet. Der Defaultwert ist `True`.

                  ListFeature.SUPPORTS_SET)
              .createTestSuite());
    }
    return suite;
  }

  // Test generators.  To let the GWT test suite generator access them, they need to be
  // public named classes with a public default constructor.

  public static final class IntsAsListGenerator extends TestIntegerListGenerator {
    @Override
    protected List<Integer> create(Integer[] elements) {
      return asList(elements);

                  ListFeature.SUPPORTS_SET)
              .createTestSuite());
    }
    return suite;
  }

  // Test generators.  To let the GWT test suite generator access them, they need to be
  // public named classes with a public default constructor.

  public static final class BytesAsListGenerator extends TestByteListGenerator {
    @Override
    protected List<Byte> create(Byte[] elements) {
      return asList(elements);
    }

                  ListFeature.SUPPORTS_SET)
              .createTestSuite());
    }
    return suite;
  }

  // Test generators.  To let the GWT test suite generator access them, they need to be
  // public named classes with a public default constructor.

  public static final class LongsAsListGenerator extends TestLongListGenerator {
    @Override
    protected List<Long> create(Long[] elements) {
      return asList(elements);
    }

Not all client code is compiled with NullAway.
Do not make a parameter `@Nullable` just to check and throw a `NullPointerException` when it is `null`. 

## Status

ACCEPTED

## Consequences

* Classes are forced to have consistent nullability annotations.
* IDE warnings become more accurate, reducing warnings fatigue.
* Public API nullability annotations become closer to reality.

        <module name="UnusedImports"/>
        <module name="IllegalImport">
            <!--
                We shouldn't use jdk.internal types.

                com.beust and org.testng.collections has classes that look like Guava.
            -->
            <property name="illegalPkgs" value="jdk.internal,com.beust,org.testng.collections"/>
            <!--
                We prefer org.jspecify for nullability annotations.

 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *

 * multimap's iterators would propagate through the keys and values in sorted order.
 *
 * <p>Keys and values may be null, as long as the underlying collection classes support null
 * elements.
 *
 * <p>The collections created by {@link #createCollection()} may or may not allow duplicates. If the
 * collection, such as a {@link Set}, does not support duplicates, an added key-value pair will