code: public ListApiKeysResult withApiKeys(ApiKey... apiKeys) {
          if (this.apiKeys == null) {
              setApiKeys(new java.util.ArrayList<ApiKey>(apiKeys.length));
          }
          for (ApiKey ele : apiKeys) {
              this.apiKeys.add(ele);
          }
          return this;
      }
docs: <p>
  The <code>ApiKey</code> objects.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setApiKeys(java.util.Collection)} or {@link #withApiKeys(java.util.Collection)} if you want to override
  the existing values.
  </p>
  
  @param apiKeys
  The <code>ApiKey</code> objects.
  @return Returns a reference to this object so that method calls can be chained together.