return null;
      }
      if (systemLoader != null) {
        try {
          return systemLoader.loadClass(FINALIZER_CLASS_NAME);
        } catch (ClassNotFoundException e) {
          // Ignore. Finalizer is simply in a child class loader.
          return null;
        }
      } else {
        return null;
      }
    }
  }

  /**

     * value is undefined.
     *
     * @return The location of the problem, never {@code null}.
     */
    String getLocation();

    /**
     * Gets the exception that caused this problem (if any).
     *
     * @return The exception that caused this problem or {@code null} if not applicable.
     */
    Exception getException();

    /**
     * Gets the message that describes this problem.

        Metadata repoMetadata = metadata.getMetadata();
        String version = null;
        if (repoMetadata != null && repoMetadata.getVersioning() != null) {
            version = constructVersion(repoMetadata.getVersioning(), artifact.getBaseVersion());
        }

        if (version == null) {
            // use the local copy, or if it doesn't exist - go to the remote repo for it

    assertEquals(1, getMultiset().remove(null, 2));
    assertFalse(
        "multiset contains present after multiset.remove(present, 2)",
        getMultiset().contains(null));
    assertEquals(0, getMultiset().count(null));
  }

  @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_QUERIES})
  public void testRemove_nullAbsent() {
    assertEquals(0, getMultiset().remove(null, 2));
  }

    assertEquals(1, getMultiset().remove(null, 2));
    assertFalse(
        "multiset contains present after multiset.remove(present, 2)",
        getMultiset().contains(null));
    assertEquals(0, getMultiset().count(null));
  }

  @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_QUERIES})
  public void testRemove_nullAbsent() {
    assertEquals(0, getMultiset().remove(null, 2));
  }

        Activation activation = profile.getActivation();

        if (activation == null) {
            return false;
        }

        String jdk = activation.getJdk();

        if (jdk == null) {
            return false;
        }

        String version = context.getSystemProperties().get("java.version");

        if (version == null || version.length() <= 0) {

    Cell[] as;
    long b, v;
    int[] hc;
    Cell a;
    int n;
    if ((as = cells) != null || !casBase(b = base, b + x)) {
      boolean uncontended = true;
      if ((hc = threadHashCode.get()) == null
          || as == null
          || (n = as.length) < 1
          || (a = as[(n - 1) & hc[0]]) == null
          || !(uncontended = a.cas(v = a.value, v + x))) retryUpdate(x, hc, uncontended);
    }
  }

            "8.8.0", "8.9.0",
            "9.0.0-alpha01", "9.0.0-beta01", "9.0.0-rc01"
        ].shuffled()

        when:
        def selected = UpdateAgpVersions.selectVersionsFrom(gradleVersion, null, allVersions)

        then:
        selected == ["8.9.0", "9.0.0-rc01"]
    }

    def "selects matching gradle major versions when stable or rc available (minimumSupported=#minimumSupported)"() {
        given:

    }

    boolean isKnownType(String className) {
        return classMetaData.find(className) != null
    }

    gradlebuild.docs.dsl.docbook.model.ClassDoc findClassDoc(String className) {
        gradlebuild.docs.dsl.docbook.model.ClassDoc classDoc = classes[className]
        if (classDoc == null && getFileForClass(className).isFile()) {
            return getClassDoc(className)
        }
        return classDoc

            }
        }
        // maven.config; if exists
        Path mavenConfig = context.rootDirectory != null ? context.rootDirectory.resolve(".mvn/maven.config") : null;
        if (mavenConfig != null && Files.isRegularFile(mavenConfig)) {
            result.add(parseMavenConfigOptions(mavenConfig));
        }
        return LayeredMavenOptions.layerMavenOptions(result);
    }