import java.util.stream.Collectors;

class Utils {
    static <T> T nonNull(T t) {
        if (t == null) {
            throw new IllegalArgumentException();
        }
        return t;
    }

    static <T> T nonNull(T t, String name) {
        if (t == null) {
            throw new IllegalArgumentException(name + " cannot be null");
        }
        return t;
    }

    static <T> T cast(Class<T> clazz, Object o, String name) {

   *
   * @param expression a boolean expression
   * @throws IllegalArgumentException if {@code expression} is false
   */
  public static void checkArgument(boolean expression) {
    if (!expression) {
      throw new IllegalArgumentException();
    }
  }

  /**
   * Ensures the truth of an expression involving one or more parameters to the calling method.

   * Entries appear in the result {@code ImmutableBiMap} in encounter order.
   *
   * <p>If the mapped keys or values contain duplicates (according to {@link
   * Object#equals(Object)}), an {@code IllegalArgumentException} is thrown when the collection
   * operation is performed. (This differs from the {@code Collector} returned by {@link
   * Collectors#toMap(Function, Function)}, which throws an {@code IllegalStateException}.)
   *

          ToOptionalState::getOptional,
          Collector.Characteristics.UNORDERED);

  /**
   * A collector that converts a stream of zero or one elements to an {@code Optional}.
   *
   * @throws IllegalArgumentException if the stream consists of two or more elements.
   * @throws NullPointerException if any element in the stream is {@code null}.
   * @return {@code Optional.of(onlyElement)} if the stream has exactly one element (must not be

        if (relativeSource.isAbsolute()) {
            throw new IllegalArgumentException("Supplied URI is not relative");
        }
        URI source = baseURI.resolve(relativeSource);
        if (!source.toASCIIString().startsWith(baseURI.toASCIIString())) {
            throw new IllegalArgumentException("Supplied relative URI escapes baseUrl");
        }
        GetTask getTask = new GetTask(source);

    if (!safe) {
      throw conflictException(conflictDescription, entry1, entry2);
    }
  }

  static IllegalArgumentException conflictException(
      String conflictDescription, Object entry1, Object entry2) {
    return new IllegalArgumentException(
        "Multiple entries with same " + conflictDescription + ": " + entry1 + " and " + entry2);
  }

  /**

   * elements. The generated map is sorted by the specified comparator.
   *
   * <p>If the mapped keys contain duplicates (according to the specified comparator), an {@code
   * IllegalArgumentException} is thrown when the collection operation is performed. (This differs
   * from the {@code Collector} returned by {@link Collectors#toMap(Function, Function)}, which
   * throws an {@code IllegalStateException}.)
   *

                        } else {
                            throw new IllegalArgumentException("Unrecognized entry: " + l);
                        }
                        String[] parts = l.split(splitExpr);
                        if (parts.length < 1) {
                            throw new IllegalArgumentException("Unrecognized entry: " + l);
                        }

      // the range have a lower bound
      throw new IllegalArgumentException(
          "Neither the DiscreteDomain nor this range set are bounded below");
    } else if (!span.hasUpperBound()) {
      try {
        domain.maxValue();
      } catch (NoSuchElementException e) {
        throw new IllegalArgumentException(
            "Neither the DiscreteDomain nor this range set are bounded above");
      }

        Reader reader = request.getReader();
        InputStream inputStream = request.getInputStream();
        if (path == null && url == null && reader == null && inputStream == null) {
            throw new IllegalArgumentException("path, url, reader or inputStream must be non null");
        }
        try {
            InputSource source = null;
            if (request.getModelId() != null || request.getLocation() != null) {