Iterator<String> iterator = asList("one", "two", "three", "four", "five").iterator();
    IllegalArgumentException expected =
        assertThrows(IllegalArgumentException.class, () -> getOnlyElement(iterator));
    assertThat(expected)
        .hasMessageThat()
        .isEqualTo("expected one element but was: <one, two, three, four, five>");
  }

        testData.add(createRelatedContent("term2", "Content for default", ""));
        mockBhv.setTestData(testData);

        int count = relatedContentHelper.load();
        assertEquals(3, count); // Three virtual host keys: "host1", "host2", ""
    }

    public void test_getHostKey_emptyVirtualHost() {
        RelatedContent entity = createRelatedContent("term", "content", "");

import org.jspecify.annotations.Nullable;

/**
 * A descriptor for a <i>discrete</i> {@code Comparable} domain such as all {@link Integer}
 * instances. A discrete domain is one that supports the three basic operations: {@link #next},
 * {@link #previous} and {@link #distance}, according to their specifications. The methods {@link
 * #minValue} and {@link #maxValue} should also be overridden for bounded types.
 *

        User user1 = createTestUser("user1", "User One");
        User user2 = createTestUser("user2", "User Two");
        User user3 = createTestUser("user3", "User Three");

        chain.update(user1);
        chain.update(user2);
        chain.update(user3);

        assertEquals(3, chain.updateCalls.size());
        assertEquals(user1, chain.updateCalls.get(0));

      this.elements = elements;
      this.duplicate = duplicate;
    }
  }

  /**
   * @return an array of the proper size with a duplicate element. The size must be at least three.
   */
  protected ArrayWithDuplicate<E> createArrayWithDuplicateElement() {
    E[] elements = createSamplesArray();
    E duplicate = elements[(elements.length / 2) - 1];

    /** The next byte to read. This is always less than or equal to [upstreamPos]. */
    private var sourcePos = 0L

    /**
     * Selects where to find the bytes for a read and read them. This is one of three sources.
     *
     * ## Upstream
     *
     * In this case the current thread is assigned as the upstream reader. We read bytes from

   */
  public static <T extends @Nullable Object> Iterable<T> concat(
      Iterable<? extends T> a, Iterable<? extends T> b) {
    return FluentIterable.concat(a, b);
  }

  /**
   * Combines three iterables into a single iterable. The returned iterable has an iterator that
   * traverses the elements in {@code a}, followed by the elements in {@code b}, followed by the

 * host platform (like Android). In July 2018 Android had 134 trusted root certificates for its HTTP
 * clients to trust.
 *
 * For example, in order to establish a secure connection to `https://www.squareup.com/`,
 * these three certificates are used.
 *
 * ```
 * www.squareup.com certificate:
 *
 * Common Name: www.squareup.com
 * Subject Alternative Names: www.squareup.com, squareup.com, account.squareup.com...

import org.jspecify.annotations.Nullable;

/**
 * A descriptor for a <i>discrete</i> {@code Comparable} domain such as all {@link Integer}
 * instances. A discrete domain is one that supports the three basic operations: {@link #next},
 * {@link #previous} and {@link #distance}, according to their specifications. The methods {@link
 * #minValue} and {@link #maxValue} should also be overridden for bounded types.
 *

  /*
   * Since Quantiles provides a fluent-style API, each test covers a chain of methods resulting in
   * the computation of one or more quantiles (or in an error) rather than individual methods. The
   * tests are divided into three sections:
   * 1. Tests on a hardcoded dataset for chains starting with median(), quartiles(), and scale(10);
   * 2. Tests on hardcoded datasets include non-finite values for chains starting with scale(10);