code: public AudioChannelMapping withInputChannelLevels(InputChannelLevel... inputChannelLevels) {
          if (this.inputChannelLevels == null) {
              setInputChannelLevels(new java.util.ArrayList<InputChannelLevel>(inputChannelLevels.length));
          }
          for (InputChannelLevel ele : inputChannelLevels) {
              this.inputChannelLevels.add(ele);
          }
          return this;
      }
docs: Indices and gain values for each input channel that should be remixed into this output channel.
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setInputChannelLevels(java.util.Collection)} or {@link #withInputChannelLevels(java.util.Collection)} if
  you want to override the existing values.
  </p>
  
  @param inputChannelLevels
  Indices and gain values for each input channel that should be remixed into this output channel.
  @return Returns a reference to this object so that method calls can be chained together.