}

  /**
   * Atomically adds the given value to the element at index {@code i}.
   *
   * @param i the index
   * @param delta the value to add
   * @return the previous value
   */
  @CanIgnoreReturnValue
  public final double getAndAdd(int i, double delta) {
    return getAndAccumulate(i, delta, Double::sum);
  }

  /**
   * Atomically adds the given value to the element at index {@code i}.

import java.util.function.LongBinaryOperator;
import java.util.function.LongUnaryOperator;
import org.jspecify.annotations.Nullable;

/**
 * A map containing {@code long} values that can be atomically updated. While writes to a
 * traditional {@code Map} rely on {@code put(K, V)}, the typical mechanism for writing to this map
 * is {@code addAndGet(K, long)}, which adds a {@code long} to the value currently associated with

 * so.
 */
@SuppressWarnings("SunApi") // b/345822163
@GwtIncompatible
abstract class Striped64 extends Number {
  /*
   * This class maintains a lazily-initialized table of atomically
   * updated variables, plus an extra "base" field. The table size
   * is a power of two. Indexing uses masked per-thread hash codes.
   * Nearly all declarations in this class are package-private,

       * This lock is used to ensure safe and correct cancellation, it ensures that a new task is
       * not scheduled while a cancel is ongoing. Also it protects the currentFuture variable to
       * ensure that it is assigned atomically with being scheduled.
       */
      private final ReentrantLock lock = new ReentrantLock();

      /** The future that represents the next execution of this task. */
      @GuardedBy("lock")

       * This lock is used to ensure safe and correct cancellation, it ensures that a new task is
       * not scheduled while a cancel is ongoing. Also it protects the currentFuture variable to
       * ensure that it is assigned atomically with being scheduled.
       */
      private final ReentrantLock lock = new ReentrantLock();

      /** The future that represents the next execution of this task. */
      @GuardedBy("lock")

      E e;
      while (n < maxElements && (e = q.poll()) != null) {
        c.add(e);
        ++n;
      }
      return n;
    } finally {
      monitor.leave();
    }
  }

  /**
   * Atomically removes all of the elements from this queue. The queue will be empty after this call
   * returns.
   */
  @Override
  public void clear() {
    Monitor monitor = this.monitor;
    monitor.enter();
    try {

   * instance, so it can be invoked again to create multiple independent maps.
   *
   * <p>The bulk operations {@code putAll}, {@code equals}, and {@code clear} are not guaranteed to
   * be performed atomically on the returned map. Additionally, {@code size} and {@code
   * containsValue} are implemented as bulk read operations, and thus may fail to observe concurrent
   * writes.
   *

  public String toString() {
    Monitor monitor = this.monitor;
    monitor.enter();
    try {
      return super.toString();
    } finally {
      monitor.leave();
    }
  }

  /**
   * Atomically removes all of the elements from this queue. The queue will be empty after this call
   * returns.
   */
  @Override
  public void clear() {
    E[] items = this.items;
    Monitor monitor = this.monitor;

      }
    }

    /**
     * Apply inbound settings and send an acknowledgement to the peer that provided them.
     *
     * We need to apply the settings and ack them atomically. This is because some HTTP/2
     * implementations (nghttp2) forbid peers from taking advantage of settings before they have
     * acknowledged! In particular, we shouldn't send frames that assume a new `initialWindowSize`

 *  Fix: Don't lose HTTP/2 flow control bytes when incoming data races with a stream close. If this
    happened enough then eventually the connection would stall.

 *  Fix: Acknowledge and apply inbound HTTP/2 settings atomically. Previously we had a race where we
    could use new flow control capacity before acknowledging it, causing strict HTTP/2 servers to
    fail the call.


## Version 4.1.1

_2019-09-05_