return null;
    }
    int mask = tableSize - 1;
    Builder.DuplicateKey duplicateKey = null;
    if (tableSize <= BYTE_MAX_SIZE) {
      /*
       * Use 8 bits per entry. The value is unsigned to allow use up to a size of 2^8.
       *
       * The absent indicator of -1 signed becomes 2^8 - 1 unsigned, which reduces the actual max
       * size to 2^8 - 1. However, due to a load factor < 1 the limit is never approached.

    private final List<Range<C>> ranges;

    public Builder() {
      this.ranges = Lists.newArrayList();
    }

    // TODO(lowasser): consider adding union, in addition to add, that does allow overlap

    /**
     * Add the specified range to this builder. Adjacent ranges are permitted and will be merged,
     * but overlapping ranges will cause an exception when {@link #build()} is called.
     *

    private final List<Range<C>> ranges;

    public Builder() {
      this.ranges = Lists.newArrayList();
    }

    // TODO(lowasser): consider adding union, in addition to add, that does allow overlap

    /**
     * Add the specified range to this builder. Adjacent ranges are permitted and will be merged,
     * but overlapping ranges will cause an exception when {@link #build()} is called.
     *

        <!--
            In order to build and run the tests against JDK 18+, we need to pass java.security.manager=allow, to make
            the deprecated 'java.lang.SecurityManager' available for use.
         -->
        <jdk>[18,]</jdk>
      </activation>
      <properties>
        <test.add.args>-Djava.security.manager=allow</test.add.args>
      </properties>
    </profile>
  </profiles>

 *   <li><b>Thread safety.</b> It is safe to access this collection concurrently from multiple
 *       threads.
 *   <li><b>Integrity.</b> This type cannot be subclassed outside this package (which would allow
 *       these guarantees to be violated).
 * </ul>
 *
 * <h4>"Interfaces", not implementations</h4>
 *
 * <p>These are classes instead of interfaces to prevent external subtyping, but should be thought

 *   <li><b>Thread safety.</b> It is safe to access this collection concurrently from multiple
 *       threads.
 *   <li><b>Integrity.</b> This type cannot be subclassed outside this package (which would allow
 *       these guarantees to be violated).
 * </ul>
 *
 * <h4>"Interfaces", not implementations</h4>
 *
 * <p>These are classes instead of interfaces to prevent external subtyping, but should be thought

  /** The HTTP {@code Access-Control-Allow-Headers} header field name. */
  public static final String ACCESS_CONTROL_ALLOW_HEADERS = "Access-Control-Allow-Headers";
  /** The HTTP {@code Access-Control-Allow-Methods} header field name. */
  public static final String ACCESS_CONTROL_ALLOW_METHODS = "Access-Control-Allow-Methods";
  /** The HTTP {@code Access-Control-Allow-Origin} header field name. */

   *
   * - Define putIfAbsent and replace as treating zero and absent identically (as currently
   *   implemented below). This is a bit surprising with putIfAbsent, which really becomes
   *   putIfZero.
   *
   * - Allow putIfAbsent and replace to distinguish between zero and absent, but don't implement
   *   remove(K, long). Without any two-phase operations it becomes feasible for all remaining