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);

            // Phase 3: Add plugin management to the last local parent in hierarchy
            for (Map.Entry<Path, Document> entry : pomMap.entrySet()) {
                Path pomPath = entry.getKey();
                Document pomDocument = entry.getValue();
                processedPoms.add(pomPath);

                context.info(pomPath + " (checking for plugin upgrades)");
                context.indent();

                        ImmutableTypeToInstanceMap.builder();
                    for (Object object : elements) {
                      Entry<?, ?> entry = (Entry<?, ?>) object;
                      builder.put((TypeToken) entry.getKey(), entry.getValue());
                    }
                    return (Map) builder.build();
                  }
                })
            .named("ImmutableTypeToInstanceMap")
            .withFeatures(

        if (from != null) {
            for (Map.Entry<K, ? extends Artifact> entry : from.entrySet()) {
                to.put(entry.getKey(), ArtifactUtils.copyArtifact(entry.getValue()));
            }
        }

        return to;
    }

    private static <T> List<T> copyList(List<T> original) {
        List<T> copy = null;

                            .entrySet()
                            .stream()
                            .filter(p -> p.getValue() > 1)
                            .map(Map.Entry::getKey)
                            .collect(Collectors.toSet());
                }
            }
        }
        return duplicateIds;
    }

    public List<BuildStep> sortedNodes() {

                List<Plugin> result = new ArrayList<>(src.size() + tgt.size());
                for (Map.Entry<Object, Plugin> entry : master.entrySet()) {
                    List<Plugin> pre = predecessors.get(entry.getKey());
                    if (pre != null) {
                        result.addAll(pre);
                    }
                    result.add(entry.getValue());
                }

            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;
    }

                        ImmutableClassToInstanceMap.builder();
                    for (Object object : elements) {
                      Entry<?, ?> entry = (Entry<?, ?>) object;
                      builder.put((Class) entry.getKey(), (Impl) entry.getValue());
                    }
                    return (Map) builder.build();
                  }
                })
            .named("ImmutableClassToInstanceMap")
            .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;