* have <a href="https://github.com/ben-manes/caffeine/wiki/Guava">different (usually better)
 * behavior</a> when multiple threads attempt concurrent mutations. Its equivalent to {@code
 * CacheBuilder} is its <a
 * href="https://www.javadoc.io/doc/com.github.ben-manes.caffeine/caffeine/latest/com.github.benmanes.caffeine/com/github/benmanes/caffeine/cache/Caffeine.html">{@code

    subclasses. We've restored that support!


## Version 3.13.0

_2019-02-04_

 *  **This release bumps our minimum requirements to Java 8+ or Android 5+.** Cutting off old
    devices is a serious change and we don't do it lightly! [This post][require_android_5] explains
    why we're doing this and how to upgrade.

   * ordering information is updated. This is used to avoid lock contention by recording a memento
   * of reads and delaying a lock acquisition until the threshold is crossed or a mutation occurs.
   *
   * <p>This must be a (2^n)-1 as it is used as a mask.
   */
  static final int DRAIN_THRESHOLD = 0x3F;

  /**