Spartan Java» Simple yet powerful Java programming

Asynchronous logging with log4j

2009-11-25T15:26:37Z

In case you are not doing it already, using asynchronous logging is generally a good idea. You don’t want your application to slow down if the server IO is a little behind flushing all that logging to the filesystem. By making it asynchronous your application can continue running without having to wait for the log [...]

View Androids emulator log from Eclipse

2009-11-19T14:07:58Z

Sounds like it should be quite straightforward, right? Well, it is, but for some reason it took me more than a few minutes (maybe I need to get more sleep :P). Anyway, to view Androids emulator log from Eclipse go to Window / Show View / Other… / Android / LogCat

Get a web page programatically from Android

2009-11-19T13:37:07Z

The Google folks were kind enough to include a version of the Apache HTTP Client in the Android SDK, ergo loading a web resource/page from our Android apps is really simple: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 HttpClient httpClient = new DefaultHttpClient(); HttpContext localContext = new BasicHttpContext(); HttpGet httpGet = new HttpGet("http://www.spartanjava.com"); HttpResponse response = httpClient.execute(httpGet, localContext); String result = ""; BufferedReader reader = new BufferedReader( [...]

Super simple AJAX for Java apps using JQuery and JSON

2009-10-28T15:46:17Z

Back in April I wrote about Java to/from JSON serialization using XStream. After developing several AJAX applications using PHP and JQuery, I found that for a lot of scenarios a very simple approach is not only easy but very effective. In the case of PHP, you can effectively enable AJAX in your apps using jQuerys [...]

Obovweb source code – a Google Appengine sample

2009-10-20T16:50:43Z

Someone asked me about the implementation details of the Google Appengine sample I published a few weeks ago (http://obovweb.appspot.com/). Well, you can get a hold of the source code here. There’s not much to tell, apart from the specific HMAC-SHA1 implementation (which you can check out in Obovs source code) it’s a very simple JSP/DWR application.

Enabling “Enter” in a form without a submit button

2009-10-13T16:27:52Z

I find it quite annoying when I can’t post/confirm a web form using the Enter key. Here is a nifty little javascript trick to do it when you do not need/want a submit input in your html. First include this javascript function somewhere accesible for your HTML: 1 2 3 4 5 6 7 8 9 10 11 12 function submitenter(e, action) { var keycode; if (window.event) [...]

Building androids

2009-09-04T14:52:19Z

I’ve been trying out the Google Android platform, and I have to say I’m quite pleased with it. The bundled Java API and VM seem to work very well and the development tools (Eclipse plugin and SDK) work just fine. You can tell a lot of thought has been put into the API and the proposed [...]

Blocking multiple clicks real easy

2009-08-10T20:00:09Z

I’ve faced this problem a few times before, but this time I decided to find a generic solution to it. I needed to prevent users from clicking action links in a web application multiple times and therefore triggering some server side action a lot of times when only one time was enough/needed. After looking around for [...]

Java application as a MS Windows service

2009-07-29T21:18:28Z

It’s really annoying to run something interactively on MS Windows when you know deep inside it should be an OS Service. Doing this on a *nix system is quite simple (most of the times you just need to write a short shell script), but on MS Windows it’s not so easy. Anyway, after looking into a [...]

Trying out Google Appengine – OTP generation app

2009-07-15T21:29:53Z

I decided to try out the new Java based version of Google Appengine. So i wrote a very simple web app that allows the user to generate one time passwords (OTP) using the HMAC-SHA1 algortihm (see OATH). You can check it out at http://obovweb.appspot.com. As the name suggests its based on my obov library. Anyway, back to [...]