code: public GetCurrentMetricDataRequest withGroupings(String... groupings) {
          if (this.groupings == null) {
              setGroupings(new java.util.ArrayList<String>(groupings.length));
          }
          for (String ele : groupings) {
              this.groupings.add(ele);
          }
          return this;
      }
docs: <p>
  The grouping applied to the metrics returned. For example, when grouped by QUEUE, the metrics returned apply to
  each queue rather than aggregated for all queues. If you group by CHANNEL, you should include a Channels filter.
  The only supported channel is VOICE.
  </p>
  <p>
  If no <code>Grouping</code> is included in the request, a summary of <code>CurrentMetrics</code> is returned.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setGroupings(java.util.Collection)} or {@link #withGroupings(java.util.Collection)} if you want to
  override the existing values.
  </p>
  
  @param groupings
  The grouping applied to the metrics returned. For example, when grouped by QUEUE, the metrics returned
  apply to each queue rather than aggregated for all queues. If you group by CHANNEL, you should include a
  Channels filter. The only supported channel is VOICE.</p>
  <p>
  If no <code>Grouping</code> is included in the request, a summary of <code>CurrentMetrics</code> is
  returned.
  @return Returns a reference to this object so that method calls can be chained together.
  @see Grouping