@Nonnull
    @Override
    public Map<String, String> getUserProperties() {
        return Collections.unmodifiableMap(new PropertiesAsMap(getMavenSession().getUserProperties()));
    }

    @Nonnull
    @Override
    public Map<String, String> getSystemProperties() {
        return Collections.unmodifiableMap(new PropertiesAsMap(getMavenSession().getSystemProperties()));
    }

    @Nonnull
    @Override

    add(primToWrap, wrapToPrim, short.class, Short.class);
    add(primToWrap, wrapToPrim, void.class, Void.class);

    PRIMITIVE_TO_WRAPPER_TYPE = Collections.unmodifiableMap(primToWrap);
    WRAPPER_TO_PRIMITIVE_TYPE = Collections.unmodifiableMap(wrapToPrim);
  }

  private static void add(
      Map<Class<?>, Class<?>> forward,
      Map<Class<?>, Class<?>> backward,
      Class<?> key,
      Class<?> value) {

        // by getMessageByCode
        errorCodeMessagesTmp.put(0, "NT_STATUS_SUCCESS");

        errorCodeMessages = Collections.unmodifiableMap(errorCodeMessagesTmp);
        dosErrorCodeStatuses = Collections.unmodifiableMap(dosErrorCodeStatusesTmp);

        final Map<Integer, String> winErrorCodeMessagesTmp = new HashMap<>();
        for (int i = 0; i < WINERR_CODES.length; i++) {

public abstract class ForwardingImmutableMap<K, V> extends ImmutableMap<K, V> {

  final transient Map<K, V> delegate;

  ForwardingImmutableMap(Map<? extends K, ? extends V> delegate) {
    this.delegate = Collections.unmodifiableMap(delegate);
  }

  @SuppressWarnings("unchecked")
  ForwardingImmutableMap(boolean throwIfDuplicateKeys, Entry<? extends K, ? extends V>... entries) {
    Map<K, V> delegate = Maps.newLinkedHashMap();

            }
        }

        this.lifecycle = new Lifecycle(
                id,
                Collections.unmodifiableList(Arrays.asList(phases)),
                defaultBindings == null ? null : Collections.unmodifiableMap(defaultBindings));
    }

    @Override
    public Lifecycle get() {
        return lifecycle;
    }

    /**
     * Ctor to be used in Java code/providers.
     */
    public DefaultLifecycleMapping(final List<Lifecycle> lifecycles) {
        this.lifecycleMap =
                Collections.unmodifiableMap(lifecycles.stream().collect(toMap(Lifecycle::getId, identity())));
    }

    /**
     * Plexus: Populates the lifecycle map from the injected list of lifecycle mappings (if not already done).
     */

        }

        Lifecycle lifecycle = new Lifecycle();
        lifecycle.setId("default");
        lifecycle.setLifecyclePhases(Collections.unmodifiableMap(lifecyclePhaseBindings));

        this.lifecycleMapping = new DefaultLifecycleMapping(Collections.singletonList(lifecycle));
    }

    @Override
    public LifecycleMapping get() {

            final Map.Entry entry = (Map.Entry) entries.next();
            entry.setValue(Collections.unmodifiableList((List) entry.getValue()));
        }
        return headerFields = Collections.unmodifiableMap(map);
    }

    @Override
    public Map getHeaderFields() {
        if (headerFields != null) {
            return headerFields;
        }
        try {
            handshake();

     */
    TEST_RUNTIME("test-runtime", false),

    /**
     * System scope.
     */
    SYSTEM("system", false);

    private static final Map<String, DependencyScope> IDS = Collections.unmodifiableMap(
            Stream.of(DependencyScope.values()).collect(Collectors.toMap(s -> s.id, s -> s)));

    /**
     * {@return the dependency scope for the given identifier, or {@code null} if none}.

        properties.put(
                MavenArtifactProperties.CONSTITUTES_BUILD_PATH,
                String.valueOf(this.pathTypes.contains(JavaPathType.CLASSES)));
        this.properties = Collections.unmodifiableMap(properties);
    }

    @Override
    public String id() {
        return id;
    }

    @Override
    public Language getLanguage() {
        return language;
    }

    @Override