@java.lang.Override
  public boolean containsHistogram(java.lang.String key) {
    if (key == null) {
      throw new NullPointerException("map key");
    }
    return internalGetHistogram().getMap().containsKey(key);
  }
<pre>
A map from the values of the facet associated with distinct values to the
number of matching entries with corresponding value.

The key format is:

* (for string histogram) string values stored in the field.
* (for named numeric bucket) name specified in `bucket()` function, like
  for `bucket(0, MAX, "non-negative")`, the key will be `non-negative`.
* (for anonymous numeric bucket) range formatted as `&lt;low&gt;-&lt;high&gt;`, for
  example, `0-1000`, `MIN-0`, and `0-MAX`.
</pre>

<code>map&lt;string, int64&gt; histogram = 2;</code>
java-talent/proto-google-cloud-talent-v4/src/main/java/com/google/cloud/talent/v4/HistogramQueryResult.java