index archetype content

indexArchetype

using System.Globalization;
using System.IO;
using System.Linq;
using System.Text;
using System.Web;
using Examine;
using Umbraco.Core;
using System.Collections.Generic;


public class Bootstrapper : ApplicationEventHandler
{
	protected override void ApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
	{
		base.ApplicationStarted(umbracoApplication, applicationContext);
		
		ExamineManager.Instance.IndexProviderCollection["ExternalIndexer"]
			.GatheringNodeData += (sender, e) =>
			{
			  // Extract JSON properties
				var fieldKeys = e.Fields.Keys.ToArray();
				foreach (var key in fieldKeys)
				{
					var value = e.Fields[key];
					if (value.DetectIsJson())
					{
						IndexNestedObject(e.Fields, JsonConvert.DeserializeObject(value), key);
					}					
				}
			};
	}
	
	private void IndexNestedObject(Dictionary<string, string> fields, object obj, string prefix)
		{
			var objType = obj.GetType();
			if (objType == typeof (JObject))
			{
				var jObj = obj as JObject;
				if (jObj != null)
				{
					foreach (var kvp in jObj)
					{
						var propKey = prefix + "_" + kvp.Key;
						var valueType = kvp.Value.GetType();
						if (typeof (JContainer).IsAssignableFrom(valueType))
						{
							IndexNestedObject(fields, kvp.Value, propKey);
						}
						else
						{
							fields.Add(propKey, kvp.Value.ToString().StripHtml());
						}
					}
				}
			}
			else if (objType == typeof (JArray))
			{
				var jArr = obj as JArray;
				if (jArr != null)
				{
					for (var i = 0; i < jArr.Count; i++)
					{
						var itm = jArr[i];
						var propKey = prefix + "_" + i;
						var valueType = itm.GetType();
						if (typeof(JContainer).IsAssignableFrom(valueType))
						{
							IndexNestedObject(fields, itm, propKey);
						}
						else
						{
							fields.Add(propKey, itm.ToString().StripHtml());
						}
					}
				}
			}
		}
}

Hi... so what does this do?... it creates new fields in the index for all properties?