code: public void setCodecs(List<String> codecs)
      {
          if (codecs == null || codecs.isEmpty())
          {
              this.codecs = null;
              return;
          }
  
          Iterator<String> iter = codecs.iterator();
          StringBuilder buffer = new StringBuilder(iter.next());
          while (iter.hasNext())
          {
              buffer.append(",").append(iter.next());
          }
          this.codecs = buffer.toString();
      }
docs: Sets the codecs to use for the call.
  <p>
  Available since Asterisk 1.6.
  
  @param codecs list of codecs to use for the call.
  @since 1.0.0