}

        @Test
        @DisplayName("Should get and set key")
        void testKey() {
            assertNull(referralData.getKey());
            referralData.setKey("cache-key-123");
            assertEquals("cache-key-123", referralData.getKey());
        }

        @Test
        @DisplayName("Should get server")
        void testGetServer() {
            assertNull(referralData.getServer());

     *
     * @param index
     *            the index
     * @return the key at the specified index
     */
    public K getKeyAt(final int index) {
        return getEntryAt(index).getKey();
    }

    /**
     * Returns the {@link java.util.Map.Entry} at the specified index.
     *
     * @param index
     *            the index

  private static <K extends @Nullable Object, V extends @Nullable Object> Entry<K, V> entry(
      K key, V value) {
    return new AbstractMapEntry<K, V>() {
      @Override
      public K getKey() {
        return key;
      }

      @Override
      public V getValue() {
        return value;
      }
    };
  }

                    MetadataGraphVertex targetNode = e.getTarget();
                    targetNode.getMd().setArtifactScope(e.getScope());
                    targetNode.getMd().setWhy(e.getSource().getMd().toString());
                    visit(targetNode);
                }
            }
        }
        // -----------------------------------------------------------------------

        if (this.options != null) {
            for (final Entry<String, Object> entry : this.options.entrySet()) {
                ret.append(",").append(entry.getKey()).append("=").append(entry.getValue());
            }
        }
        ret.append("]");
        return ret.toString();
    }

            return size;
        }
        if (obj instanceof Map<?, ?>) {
            long size = 0;
            for (final Map.Entry<?, ?> entry : ((Map<?, ?>) obj).entrySet()) {
                size += sizeOf(entry.getKey());
                size += sizeOf(entry.getValue());
            }
            return size;
        }
        return 16L;
    }

                    for (Object object : elements) {
                      Entry<Class, Impl> entry = (Entry<Class, Impl>) object;
                      map.putInstance(entry.getKey(), entry.getValue());
                    }
                    return (Map) map;
                  }
                })
            .named("MutableClassToInstanceMap")
            .withFeatures(

          Map.Entry<E, Integer> mapEntry = backingEntries.next();
          return new Multisets.AbstractEntry<E>() {
            @Override
            public E getElement() {
              return mapEntry.getKey();
            }

            @Override
            public int getCount() {
              Integer frequency = backingMap.get(getElement());
              return (frequency == null) ? 0 : frequency;

            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);

        // 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(