"Should not contain null after unsupported putIfAbsent(present, null)");
  }

  @CanIgnoreReturnValue
  private V putIfAbsent(Entry<K, V> entry) {
    return getMap().putIfAbsent(entry.getKey(), entry.getValue());
  }

    void setReleaseUpdatePolicy(ArtifactRepositoryPolicy policy);

    ArtifactRepositoryLayout getLayout();

    void setLayout(ArtifactRepositoryLayout layout);

    String getKey();

    @Deprecated
    boolean isUniqueVersion();

    @Deprecated
    boolean isBlacklisted();

    @Deprecated
    void setBlacklisted(boolean blackListed);

    /**

      Collection<? extends Entry<? extends K, ? extends V>> entries) {
    HashMap<K, V> map = new HashMap<>();
    for (Entry<? extends K, ? extends V> entry : entries) {
      map.put(entry.getKey(), entry.getValue());
    }
    return map;
  }

        // populate the provides section
        Properties provides = model.getProvides();
        for (Entry<Object, Object> provide : provides.entrySet()) {
            String key = (String) provide.getKey();
            String value = (String) provide.getValue();

            if (value == null) {
                throw new MisconfiguredToolchainException(

        classes.put(fullyQualifiedClassName, metaData);
    }

    @Override
    public void each(Closure cl) {
        for (Map.Entry<String, T> entry : classes.entrySet()) {
            cl.call(new Object[]{entry.getKey(), entry.getValue()});
        }
    }

    public void each(Action<? super T> action) {
        for (T t : classes.values()) {
            action.execute(t);
        }
    }

    @SuppressWarnings("unchecked") // we'll only be using getKey and getValue, which are covariant
    Entry<K, V>[] entryArray = (Entry<K, V>[]) Iterables.toArray(entries, EMPTY_ENTRY_ARRAY);
    switch (entryArray.length) {
      case 0:
        return of();
      case 1:
        Entry<K, V> entry = entryArray[0];
        return of(entry.getKey(), entry.getValue());
      default:
        /*

  public void testPut_nullValueSupported() {
    Entry<K, V> nullValueEntry = entry(k3(), null);
    assertNull(
        "putIfAbsent(key, null) should return null",
        getMap().putIfAbsent(nullValueEntry.getKey(), nullValueEntry.getValue()));
    expectAdded(nullValueEntry);
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = ZERO)

            List<Plugin> plugins = build.getPlugins();
            Map<Object, Plugin> normalized = new LinkedHashMap<>(plugins.size() * 2);

            for (Plugin plugin : plugins) {
                Object key = plugin.getKey();
                Plugin first = normalized.get(key);
                if (first != null) {
                    merger.mergePlugin(plugin, first);
                }
                normalized.put(key, plugin);

  static TestSuite tests(String name, ByteSinkFactory factory) {
    TestSuite suite = new TestSuite(name);
    for (Entry<String, String> entry : TEST_STRINGS.entrySet()) {
      String desc = entry.getKey();
      TestSuite stringSuite = suiteForString(name, factory, entry.getValue(), desc);
      suite.addTest(stringSuite);
    }
    return suite;
  }

  private static TestSuite suiteForString(

  static TestSuite tests(String name, ByteSinkFactory factory) {
    TestSuite suite = new TestSuite(name);
    for (Entry<String, String> entry : TEST_STRINGS.entrySet()) {
      String desc = entry.getKey();
      TestSuite stringSuite = suiteForString(name, factory, entry.getValue(), desc);
      suite.addTest(stringSuite);
    }
    return suite;
  }

  private static TestSuite suiteForString(