*         <li>UNSET, meaning "null pointer"
   *         <li>one plus an index into the keys, values, and entries arrays
   *       </ul>
   *   <li>another java.util.Map delegate implementation. In most modern JDKs, normal java.util hash
   *       collections intelligently fall back to a binary search tree if hash table collisions are
   *       detected. Rather than going to all the trouble of reimplementing this ourselves, we

    // We can continue if it's 1.8, and we can continue if it's an integer in [9, 20).
    if (javaVersion != null && javaVersion >= 20) {
      // TODO(b/261217224, b/361604053): Make this test work under newer JDKs.
      return;
    }
    TimedWaiterThread thread = new TimedWaiterThread(new AbstractFuture<Object>() {}, 2, SECONDS);
    thread.start();
    thread.awaitWaiting();

   *         <li>UNSET, meaning "null pointer"
   *         <li>one plus an index into the keys, values, and entries arrays
   *       </ul>
   *   <li>another java.util.Map delegate implementation. In most modern JDKs, normal java.util hash
   *       collections intelligently fall back to a binary search tree if hash table collisions are
   *       detected. Rather than going to all the trouble of reimplementing this ourselves, we

    // We can continue if it's 1.8, and we can continue if it's an integer in [9, 20).
    if (javaVersion != null && javaVersion >= 20) {
      // TODO(b/261217224, b/361604053): Make this test work under newer JDKs.
      return;
    }
    TimedWaiterThread thread = new TimedWaiterThread(new AbstractFuture<Object>() {}, 2, SECONDS);
    thread.start();
    thread.awaitWaiting();

JDK 16 and testing on a JDK 11 runtime; to do this, set `RUNTIME_JAVA_HOME`
pointing to the Java home of a JDK 11 installation. Note that this mechanism can
be used to test against other JDKs as well, this is not only limited to JDK 11.

> Note: It is also required to have `JAVA8_HOME`, `JAVA9_HOME`, `JAVA10_HOME`
and `JAVA11_HOME`, `JAVA12_HOME`, `JAVA13_HOME`, `JAVA14_HOME`, and `JAVA15_HOME`

          <type>String</type>
          <description>
            Specifies that this profile will be activated when a matching JDK is detected.
            For example, {@code 1.4} only activates on JDKs versioned 1.4,
            while {@code !1.4} matches any JDK that is not version 1.4. Ranges are supported too:
            {@code [1.5,)} activates when the JDK is 1.5 minimum.
          </description>
        </field>

    if (expectedSize < 3) {
      checkNonnegative(expectedSize, "expectedSize");
      return expectedSize + 1;
    }
    if (expectedSize < Ints.MAX_POWER_OF_TWO) {
      // This seems to be consistent across JDKs. The capacity argument to HashMap and LinkedHashMap
      // ends up being used to compute a "threshold" size, beyond which the internal table
      // will be resized. That threshold is ceilingPowerOfTwo(capacity*loadFactor), where

    if (expectedSize < 3) {
      checkNonnegative(expectedSize, "expectedSize");
      return expectedSize + 1;
    }
    if (expectedSize < Ints.MAX_POWER_OF_TWO) {
      // This seems to be consistent across JDKs. The capacity argument to HashMap and LinkedHashMap
      // ends up being used to compute a "threshold" size, beyond which the internal table
      // will be resized. That threshold is ceilingPowerOfTwo(capacity*loadFactor), where