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XPages JavaScript utility function of the day

Tue, 10 May 2011 12:05:02 GMT

Yesterday and today I've been spending some time doing some XPages coding for a customer project and after spending quite some time doing Java plugin development I'm amazed of how easy XPages are. Don't get me wrong - there is still work to do for the XPages team but it's a joy to work with XPages and coding in JavaScript is just - well - flexible and fun.

One of the real joys of JavaScript is it's dynamic nature and that it allows one to really cut down on the boilerplate and repeated code. For one I spent a lot of key pressed getting field values from backend documents in server side JavaScript. Instead of repeating the same ol' Document.getItemValueString(String) over and over again I did a neat little shortcut. Since I needed all items from a document I just created a utility function to JSONify a document to make it easier to access. The method is below.

var jsonifyDocument = function(doc) {
   var result = {};
   if (!doc) return result;
   var item;
   for (item in doc.getItems().toArray()) {
      result[item.getName().toLowerCase()] = item.getText();
   }
   return result;
};

So now instead of writing doc.getItemValueString all the time I can now just do property-like access to field values ("Heading" and "Description" are fields on the document).

var jsonDoc = jsonifyDocument(doc);
jsonDoc.heading + " (" + jsonDoc.description + ")";

I also wrote a nice little Dojo-like mixin function to make my XAgents easy to configure. But that's for another day.

Messing with JSON?

Thu, 17 Jul 2008 05:02:00 GMT

Working with JSON can be a little tricky since it normally comes in as one long string which means it can be difficult to discover the data structure. I ran into this while pasing the search.twitter.com JSON API and needed a JSON viewer to help me out. A quick Google search later I found JsonViewer which is a very nice small utility for perusing JSON data. No install necessary.

If you're working with JSON check it out.

JSONMap class

Mon, 19 Feb 2007 10:25:03 GMT

I'm starting off with converting some inhouse developed AJAX stuff to using DOJO and for that reason I needed to convert my XML responses to JSON. Using the JSON Java classes this was pretty straight forward but I really needed an easier way to convert a java.util.Map instance to JSON. Extending JSONArray this was easy. Provided here for those who might need similar code...

package org.json;

import java.util.Iterator;
import java.util.Map;

public class JSONMap extends JSONArray {
   public JSONMap(Map m) {
      for (Iterator ite=m.keySet().iterator(); ite.hasNext(); ) {
         String key = (String)ite.next();
         String value = m.get(key).toString();
         JSONArray a = new JSONArray();
         a.put(value);
         a.put(key);
         this.put(a);
      }
   }
}

Code like this

Map m = new HashMap();
m.put("AL", "Alabama");
m.put("AK", "Alaska");
m.put("AR", "Arkansas");
JSONMap jm = new JSONMap(m);
System.out.println(jm.toString());

will output the following JSON

[
    [ "Alabama", "AL" ],
    [ "Alaska", "AK" ],
    [ "Arkansas", "AR" ]
]