* (such as an XML document). Typically (but not always), the inverse process of "unescaping" the
 * text is performed automatically by the relevant parser.
 *
 * <p>For example, an XML escaper would convert the literal string {@code "Foo<Bar>"} into {@code
 * "Foo&lt;Bar&gt;"} to prevent {@code "<Bar>"} from being confused with an XML tag. When the

  public static final MediaType OGG_CONTAINER = createConstant(APPLICATION_TYPE, "ogg");
  public static final MediaType OOXML_DOCUMENT =
      createConstant(
          APPLICATION_TYPE, "vnd.openxmlformats-officedocument.wordprocessingml.document");
  public static final MediaType OOXML_PRESENTATION =
      createConstant(

 *
 * <p>HTML escaping is particularly tricky: For example, <a href="http://goo.gl/5TgZb">some
 * elements' text contents must not be HTML escaped</a>. As a result, it is impossible to escape an
 * HTML document correctly without domain-specific knowledge beyond what {@code HtmlEscapers}
 * provides. We strongly encourage the use of HTML templating systems.
 *
 * @author Sven Mawson
 * @author David Beaumont
 * @since 15.0
 */

   * "plain {@code T}." This API provides that.
   */
  @SuppressWarnings({"nullness", "TypeParameterUnusedInFormals", "ReturnMissingNullable"})
  // The warnings are legitimate. Each time we use this method, we document why.
  @ParametricNullness
  static <T extends @Nullable Object> T uncheckedNull() {
    return null;
  }

  private NullnessCasts() {}

 * non-ASCII characters to their numeric entity replacements. These XML escapers provide the minimal
 * level of escaping to ensure that the output can be safely included in a Unicode XML document.
 *
 * <p>For details on the behavior of the escapers in this class, see sections <a
 * href="http://www.w3.org/TR/2008/REC-xml-20081126/#charsets">2.2</a> and <a

 * (such as an XML document). Typically (but not always), the inverse process of "unescaping" the
 * text is performed automatically by the relevant parser.
 *
 * <p>For example, an XML escaper would convert the literal string {@code "Foo<Bar>"} into {@code
 * "Foo&lt;Bar&gt;"} to prevent {@code "<Bar>"} from being confused with an XML tag. When the

   *
   * - The map has not switched to delegating to a java.util implementation to mitigate hash
   *   flooding. Callers can confirm this by null-checking delegateOrNull().
   *
   * In an ideal world, we would document why we know those things are true every time we call these
   * methods. But that is a bit too painful....
   */

  private Object requireTable() {
    return requireNonNull(table);
  }

  @SuppressWarnings({"nullness", "TypeParameterUnusedInFormals", "ReturnMissingNullable"})
  // The warnings are legitimate. Each time we use this method, we document why.
  @ParametricNullness
  static <T extends @Nullable Object> T unsafeNull() {
    return null;
  }

  private NullnessCasts() {}

import com.google.common.escape.Escaper;

/**
 * {@code Escaper} instances suitable for strings to be included in particular sections of URLs.
 *
 * <p>If the resulting URLs are inserted into an HTML or XML document, they will require additional
 * escaping with {@link com.google.common.html.HtmlEscapers} or {@link
 * com.google.common.xml.XmlEscapers}.
 *
 * @author David Beaumont
 * @author Chris Povirk
 * @since 15.0
 */

   *
   * <p>Some algorithms that operate on a {@code PredecessorsFunction} may produce undesired results
   * if the returned {@link Iterable} contains duplicate elements. Implementations of such
   * algorithms should document their behavior in the presence of duplicates.
   *
   * <p>The elements of the returned {@code Iterable} must each be:
   *
   * <ul>
   *   <li>Non-null