}
}

// WriteOnCloser implements io.WriteCloser and always
// executes at least one write operation if it is closed.
//
// This can be useful within the context of HTTP. At least
// one write operation must happen to send the HTTP headers
// to the peer.
type WriteOnCloser struct {
	io.Writer
	hasWritten bool
}

func (w *WriteOnCloser) Write(p []byte) (int, error) {
	w.hasWritten = true
	return w.Writer.Write(p)
}

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          within a display generated by the Derivative Works, if and
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          do not modify the License. You may add Your own attribution
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          do not modify the License. You may add Your own attribution
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          notices within Derivative Works that You distribute, alongside

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          within a display generated by the Derivative Works, if and
          wherever such third-party notices normally appear. The contents
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          do not modify the License. You may add Your own attribution
          notices within Derivative Works that You distribute, alongside

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    assertThrows(IllegalArgumentException.class, () -> multiset.add(KEY, COUNT_TO_ADD));
  }

  /**
   * Simulate some of the races that can happen on add. We can't easily simulate the race that
   * happens when an {@link AtomicInteger#compareAndSet} fails, but we can simulate the case where

 *       instance of {@link HashCode}.
 *   <li><b>pure function:</b> the value produced must depend only on the input bytes, in the order
 *       they appear. Input data is never modified. {@link HashFunction} instances should always be
 *       stateless, and therefore thread-safe.
 *   <li><b>collision-averse:</b> while it can't be helped that a hash function will sometimes

 *       instance of {@link HashCode}.
 *   <li><b>pure function:</b> the value produced must depend only on the input bytes, in the order
 *       they appear. Input data is never modified. {@link HashFunction} instances should always be
 *       stateless, and therefore thread-safe.
 *   <li><b>collision-averse:</b> while it can't be helped that a hash function will sometimes