code: public ListVoiceConnectorTerminationCredentialsResult withUsernames(String... usernames) {
          if (this.usernames == null) {
              setUsernames(new java.util.ArrayList<String>(usernames.length));
          }
          for (String ele : usernames) {
              this.usernames.add(ele);
          }
          return this;
      }
docs: <p>
  A list of user names.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setUsernames(java.util.Collection)} or {@link #withUsernames(java.util.Collection)} if you want to
  override the existing values.
  </p>
  
  @param usernames
  A list of user names.
  @return Returns a reference to this object so that method calls can be chained together.