assertArrayEquals(key, transport.getServerEncryptionKey());
        verify(transport).getServerEncryptionKey();

        // Empty array
        byte[] empty = new byte[0];
        when(transport.getServerEncryptionKey()).thenReturn(empty);
        assertArrayEquals(empty, transport.getServerEncryptionKey());

        // Null
        when(transport.getServerEncryptionKey()).thenReturn(null);

    @Nonnull
    Stream<P> problems(BuilderProblem.Severity severity);

    /**
     * Creates an "empty" problem collector that doesn't store any problems.
     *
     * @param <P> the type of problem
     * @return an empty problem collector
     */
    @Nonnull
    static <P extends BuilderProblem> ProblemCollector<P> empty() {
        return new ProblemCollector<>() {
            @Override

     *
     * @param baseDirectory the base directory for relativizing paths during matching
     * @param includes the patterns of files to include, or null/empty for including all files
     * @param excludes the patterns of files to exclude, or null/empty for no exclusion
     * @param useDefaultExcludes whether to augment excludes with default SCM exclusion patterns

   *     // operate on tuple
   *   }
   * }
   * }
   *
   * <p>Note that if any input set is empty, the Cartesian product will also be empty. If no sets at
   * all are provided (an empty list), the resulting Cartesian product has one element, an empty
   * list (counter-intuitive, but mathematically consistent).
   *

     * The default value is empty.
     */
    default Optional<String> module() {
        return Optional.empty();
    }

    /**
     * {@return the version of the platform where the code will be executed}.
     * In a Java environment, this is the value of the {@code --release} compiler option.
     * The default value is empty.
     */
    default Optional<Version> targetVersion() {

  public void testConcat() {
    assertThat(Floats.concat()).isEqualTo(EMPTY);
    assertThat(Floats.concat(EMPTY)).isEqualTo(EMPTY);
    assertThat(Floats.concat(EMPTY, EMPTY, EMPTY)).isEqualTo(EMPTY);
    assertThat(Floats.concat(ARRAY1)).isEqualTo(ARRAY1);
    assertThat(Floats.concat(ARRAY1)).isNotSameInstanceAs(ARRAY1);
    assertThat(Floats.concat(EMPTY, ARRAY1, EMPTY)).isEqualTo(ARRAY1);

  }

  public void testConcat() {
    assertThat(Ints.concat()).isEqualTo(EMPTY);
    assertThat(Ints.concat(EMPTY)).isEqualTo(EMPTY);
    assertThat(Ints.concat(EMPTY, EMPTY, EMPTY)).isEqualTo(EMPTY);
    assertThat(Ints.concat(ARRAY1)).isEqualTo(ARRAY1);
    assertThat(Ints.concat(ARRAY1)).isNotSameInstanceAs(ARRAY1);
    assertThat(Ints.concat(EMPTY, ARRAY1, EMPTY)).isEqualTo(ARRAY1);
    assertThat(Ints.concat(ARRAY1, ARRAY1, ARRAY1))

  public void testConcat() {
    assertThat(Floats.concat()).isEqualTo(EMPTY);
    assertThat(Floats.concat(EMPTY)).isEqualTo(EMPTY);
    assertThat(Floats.concat(EMPTY, EMPTY, EMPTY)).isEqualTo(EMPTY);
    assertThat(Floats.concat(ARRAY1)).isEqualTo(ARRAY1);
    assertThat(Floats.concat(ARRAY1)).isNotSameInstanceAs(ARRAY1);
    assertThat(Floats.concat(EMPTY, ARRAY1, EMPTY)).isEqualTo(ARRAY1);

    @Nonnull
    <T> T lookup(Class<T> type, String name);

    /**
     * Performs a lookup for optional typed component.
     *
     * @param type The component type.
     * @return Optional carrying component or empty optional if no such component.
     * @param <T> The component type.
     * @throws LookupException if there is some provisioning related issue.
     */
    @Nonnull
    <T> Optional<T> lookupOptional(Class<T> type);

     * format using the specified encoding scheme.
     *
     * @param s
     *            The string to be converted. Must not be {@literal null} or empty.
     * @param enc
     *            The encoding scheme. Must not be {@literal null} or empty.
     * @return The string encoded in <code>application/x-www-form-urlencoded</code> format.
     */
    public static String encode(final String s, final String enc) {