code: public DescribeMatchmakingRuleSetsResult withRuleSets(MatchmakingRuleSet... ruleSets) {
          if (this.ruleSets == null) {
              setRuleSets(new java.util.ArrayList<MatchmakingRuleSet>(ruleSets.length));
          }
          for (MatchmakingRuleSet ele : ruleSets) {
              this.ruleSets.add(ele);
          }
          return this;
      }
docs: <p>
  Collection of requested matchmaking rule set objects.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setRuleSets(java.util.Collection)} or {@link #withRuleSets(java.util.Collection)} if you want to override
  the existing values.
  </p>
  
  @param ruleSets
  Collection of requested matchmaking rule set objects.
  @return Returns a reference to this object so that method calls can be chained together.