private static List<StackTraceElement> jlaStackTrace(Throwable t) {
    checkNotNull(t);
    /*
     * TODO(cpovirk): Consider optimizing iterator() to catch IOOBE instead of doing bounds checks.
     *
     * TODO(cpovirk): Consider the UnsignedBytes pattern if it performs faster and doesn't cause
     * AOSP grief.
     */
    return new AbstractList<StackTraceElement>() {
      /*

  private static List<StackTraceElement> jlaStackTrace(Throwable t) {
    checkNotNull(t);
    /*
     * TODO(cpovirk): Consider optimizing iterator() to catch IOOBE instead of doing bounds checks.
     *
     * TODO(cpovirk): Consider the UnsignedBytes pattern if it performs faster and doesn't cause
     * AOSP grief.
     */
    return new AbstractList<StackTraceElement>() {
      /*

         *
         * 2a. If the resolved types are identical to the original types, then we can return the
         * original, identical JDK TypeVariable. By doing so, we sidestep the problem entirely.
         *
         * 2b. If the resolved types are different from the original types, things are trickier. The

      Thread.yield();
      long d = ns - (System.nanoTime() - startTime);
      if (d > 0L) millis = d / (1000 * 1000);
      else break;
    }
  }

  /** Waits out termination of a thread pool or fails doing so. */
  void joinPool(ExecutorService exec) {
    try {
      exec.shutdown();
      assertTrue(
          "ExecutorService did not terminate in a timely manner",

  private static void selectInPlace(int required, double[] array, int from, int to) {
    // If we are looking for the least element in the range, we can just do a linear search for it.
    // (We will hit this whenever we are doing quantile interpolation: our first selection finds
    // the lower value, our second one finds the upper value by looking for the next least element.)
    if (required == from) {
      int min = from;

 *
 * <h3>Non-preconditions</h3>
 *
 * <p>It is of course possible to use the methods of this class to check for invalid conditions
 * which are <i>not the caller's fault</i>. Doing so is <b>not recommended</b> because it is
 * misleading to future readers of the code and of stack traces. See <a
 * href="https://github.com/google/guava/wiki/ConditionalFailuresExplained">Conditional failures

   * TODO(b/242884182): Figure out why this helps produce the same class file when we compile most
   * of common.collect a second time with the results of the first compilation on the classpath. Or
   * just back this out once we stop doing that (which we'll do after our internal GWT setup
   * changes).
   */
  @Override
  public ImmutableMap<Object, Collection<Object>> asMap() {
    return super.asMap();
  }

  private Object readResolve() {

        companies, or even industries — utilities useful for a sizable proportion of all Java
        programmers everywhere. If you can give enough detail such that any of us can imagine coming
        across a similar need in our own work, that's extremely helpful in studying how broadly
        useful the proposed change will be.

  - type: textarea
    attributes:
      label: Concrete Use Cases

 * {@link System#currentTimeMillis()}, best represented as an {@link java.time.Instant}. Such values
 * <i>can</i> be subtracted to obtain a {@code Duration} (such as by {@code Duration.between}), but
 * doing so does <i>not</i> give a reliable measurement of elapsed time, because wall time readings
 * are inherently approximate, routinely affected by periodic clock corrections. Because this class

   * completely unused, and an expensive acquire(100) request comes. It would be nonsensical to just
   * wait for 100 seconds, and /then/ start the actual task. Why wait without doing anything? A much
   * better approach is to /allow/ the request right away (as if it was an acquire(1) request
   * instead), and postpone /subsequent/ requests as needed. In this version, we allow starting the