code: public SPropertyOrQuery byIndex(String indexName) {
  		getStartExpression().setIndexOrId(new IndexOrId(indexName));
  		SPropertyOrQuery ret = new SPropertyOrQuery(getStartExpression());
  		return ret;
  	}
docs: <div color='red' style="font-size:24px;color:red"><b><i><u>JCYPHER</u></i></b></div>
  <div color='red' style="font-size:18px;color:red"><i>choose the index to lookup</i></div>
  <div color='red' style="font-size:18px;color:red"><i>e.g. START.node(n).<b>byIndex("Person")</b></i></div>
  <br/>