* Reads the toolchains from the specified file.
     *
     * @param input The file to deserialize the toolchains from, must not be {@code null}.
     * @param options The options to use for deserialization, may be {@code null} to use the default values.
     * @return The deserialized toolchains, never {@code null}.
     * @throws IOException If the toolchains could not be deserialized.

     * @param externalRepositories The external (and already mirrored) repositories to merge into the result list, may
     *            be {@code null}.
     * @param request The project building request holding further settings like repository settings, must not be
     *            {@code null}.
     * @return The effective artifact repositories, never {@code null}.
     * @throws InvalidRepositoryException

        this.source = source;
        this.sourceModel = null;
    }

    public void setSource(Model source) {
        this.sourceModel = source;
        this.source = null;

        if (rootModel == null) {
            rootModel = source;
        }
    }

    private String getSource() {
        if (source == null && sourceModel != null) {
            source = ModelProblemUtils.toPath(sourceModel);
        }

 * <pre>{@code
 * // Find child element
 * Element child = parent.child("version").orElse(null);
 *
 * // Check if child exists
 * boolean hasVersion = parent.child("version").isPresent();
 *
 * // Get child text content
 * String version = parent.child("version")
 *     .map(Element::textContent)
 *     .orElse(null);
 *
 * // Get trimmed text content
 * String trimmedVersion = parent.child("version")

{"request":{"uri":"/2","header":{}}}`,
		},
		{
			name:  "is-not-missing-null",
			query: `select * from s3object[*] as s where s.request.header is not missing`,
			wantResult: `{"request":{"uri":"/1","header":{"User-Agent":"test"}}}
{"request":{"uri":"/2","header":null}}`,
			withJSON: `{"request":{"uri":"/1","header":{"User-Agent":"test"}}}
{"request":{"uri":"/2","header":null}}`,
		},
		{
			name:       "is-not-missing",

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

        ActivationProperty property = activation.getProperty();

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

        String name = property.getName();
        boolean reverseName = false;

        if (name != null && name.startsWith("!")) {
            reverseName = true;

    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);
    }
  }

    Map<C, V> row = safeGet(rowMap(), rowKey);
    return row != null && Maps.safeContainsKey(row, columnKey);
  }

  @Override
  public @Nullable V get(@Nullable Object rowKey, @Nullable Object columnKey) {
    Map<C, V> row = safeGet(rowMap(), rowKey);
    return (row == null) ? null : safeGet(row, columnKey);
  }

  @Override
  public boolean isEmpty() {
    return size() == 0;
  }

    List<V> values = asList(v0(), null, v3());
    multimap().replaceValues(k0(), values);
    assertGet(k0(), values);
  }

  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE, ALLOWS_NULL_KEYS})
  public void testReplaceValuesWithNullKey() {
    List<V> values = asList(v0(), v2(), v3());
    multimap().replaceValues(null, values);
    assertGet(null, values);
  }

    /**
     * GETs the source URI content as byte array. The source MUST BE relative from the {@link RemoteRepository#getUrl()}
     * root.
     *
     * @return the byte array if operation succeeded, {@code null} if source does not exist.
     * @throws RuntimeException If failed (and not due source not exists).
     */
    @Nonnull
    Optional<byte[]> getBytes(@Nonnull URI relativeSource);

    /**