Head to screen collision (H2SC)

Time cost for creating a HashSet from an ArrayList

2011-08-15T19:48:00.004+03:00

I ran this simple test to get a "feel":

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Random;

public class Test {
	public static void main(String... args) {
		List<String> bigList = new ArrayList<String>();
		List<String> smallList = new ArrayList<String>();

		Random random = new Random();

		// builds a 10000 items list made of items
		// with string values generated from random
		// numbers between 1000000 and 1999999
		// this list has a higher chance to have duplicates
		for (int i = 0; i < 10000; i++)
			smallList.add(String.valueOf(random.nextInt(1000000) + 1000000));

		// builds a 1000000 items list made of items
		// with string values generated from random
		// numbers between 1000000 and 1999999
		for (int i = 0; i < 1000000; i++)
			bigList.add(String.valueOf(random.nextInt(1000000) + 1000000));

		int tests = 100;
		
		double smallListTransformationsTotalTime = 0;
		
		for (int i = 0; i < tests; i++) {
			long start = System.currentTimeMillis();
			new HashSet<String>(smallList);
			long end = System.currentTimeMillis() - start;
			smallListTransformationsTotalTime += end;
		}		
		System.out.println("Small list transformation average: " + (smallListTransformationsTotalTime / tests));
		
		double bigListTransformationsTotalTime = 0;
		
		for (int i = 0; i < tests; i++) {
			long start = System.currentTimeMillis();
			new HashSet<String>(bigList);
			long end = System.currentTimeMillis() - start;			
			bigListTransformationsTotalTime += end;
		}
		System.out.println("Big list transformation average: " + (bigListTransformationsTotalTime / tests));		
	}
}

Running this (100 tests) on my computer (i7 quad core using eclipse) yielded the following:

Small list transformation averaged 0.81ms
Big list transformation averaged 196.31ms

Better late than never

2011-04-27T16:15:00.001+03:00

Just a shout out to my dear friend and colleague Shai Raiten for getting his MVP award for the third year in a row.

Shai is an exceptionally gifted professional, engaged in software development, consulting and lecturing on a daily basis. He is also funny as hell and fun to be around... what more can you ask for? :)

So, Mazal tov!!!

P.S See this post for the "official announcement"

Funky behavior of CSS Universal selector in Google Chrome Developer tools

2011-04-23T02:43:00.005+03:00

Although its the middle of the night and I'm in an intense work / implementation session for one of the startups I work with (zbang.it) I had to pause for this.

I was on the brink of loosing my sanity because of this weird problem where styles were merged with each other, when inspecting elements in Google Chrome developer tools (v10.0.648.205).

First, here is the style sheet (or some of it), please note the CSS Universal selector at the beginning:

*
{
    vertical-align: baseline;
    font-weight: inherit;
    font-family: inherit;
    font-style: inherit;
    font-size: 100%;
    border: 0 none;
    outline: 0;
    padding: 0;
    margin: 0;
}

body
{
    font-family: Calibari, Arial;
    font-size: 12px;
}

div.ui-layout-east
{
    width: 250px;
    float: right;
}

div.ui-innerLayout-north
{
    height: 70px;
}

.
.
. 
more css down here

Here is how it looked while inspecting div.ui-layout-east on Google Chrome developer tools:

Take a good look at the highlighted height: 70px, its jumped up from div.ui-innerLayout-north, don't believe me? I didn't believe myself at first, so I added a super noticeable style to div.ui-innerLayout-north, like so:

*
{
    vertical-align: baseline;
    font-weight: inherit;
    font-family: inherit;
    font-style: inherit;
    font-size: 100%;
    border: 0 none;
    outline: 0;
    padding: 0;
    margin: 0;
}

body
{
    font-family: Calibari, Arial;
    font-size: 12px;
}

div.ui-layout-east
{
    width: 250px;
    float: right;
}

div.ui-innerLayout-north
{
    height: 70px;
    border: 3px dashed red;
}

.
.
. 
more css down here

And, lo and behold

It jumped right up again!!!

At first I thought that I had a css syntax error somewhere but by way of elimination and after a long while I found out that this behavior happens only when the universal selector is the first style on the style sheet, and if its location changes:

body
{
    font-family: Calibari, Arial;
    font-size: 12px;
}

*
{
    vertical-align: baseline;
    font-weight: inherit;
    font-family: inherit;
    font-style: inherit;
    font-size: 100%;
    border: 0 none;
    outline: 0;
    padding: 0;
    margin: 0;
}

div.ui-layout-east
{
    width: 250px;
    float: right;
}

div.ui-innerLayout-north
{
    height: 70px;
    border: 3px dashed red;
}

.
.
. 
more css down here

The universe goes to being expected again:

By the way this does not affect the actual HTML in the browser, only the display in developer tools.

Wasted a little over an hour of my life, hope it saves you one.

Yet Another Facebook Search

2011-04-21T18:06:00.001+03:00

Hi,

Check out this website:

http://www.yetanotherfacebooksearch.com

Which helps you search facebook for people, groups and pages. You will also get relevant results about a person and his friends, outside of facebook. This facebook search doesn't requires you to login as well.

Check it out...

A simple AppEngine Guice Module (Part 1)

2011-04-02T17:09:00.000+03:00

This post is about a simple Guice AppEngine module I've written, which I find very useful, hence, I decided to share it.

The code is available here

The module will get your AppEngine project started quickly, here is a typical bootstrap (GuiceServletContextListener) code for a simple app:

package com.codeark.appengine;

import com.codeark.appengine.objectify.ObjectifyModule;
import com.google.inject.Guice;
import com.google.inject.Injector;
import com.google.inject.Module;
import com.google.inject.servlet.GuiceServletContextListener;

public class Bootstrap extends GuiceServletContextListener {

 @Override
 protected Injector getInjector() {

  Module aeModule = 
   AppEngineModule.build().withDatastoreService()
    .withUrlFetchService().withMemcacheService().withMailService();

  Module myModule = new MyOtherModule();
  
  return Guice.createInjector(aeModule, myModule);
 }
}

The module's Fluent Interface API(which I like so much) exposes a single static build() method which returns an instance of the module. You can then configure which services AppEngine should initialize using the .With*Service() methods.

later you can do:

class Classy {
 @Inject
 public Classy(MemcacheService service, MailService mail) {
 ...
 }
}

There are several other goodies included in the source, which I will discuss in later posts: A simple abstraction over UrlFetchService and an Objectify module.

null is null ?

2010-10-31T12:56:00.000+02:00

Here is a funny error message on Internet Explorer:

:-)

How does a dog shortens your notebook's battery life?

2010-10-08T03:33:00.000+02:00

So my notebook was having a severe drop in battery life. A few months ago I purchased a new battery (yes, yes...) and was quite disappointed that it had happened so quickly, however I've noticed that my cooling fan is doing overtime, even on a power saver plan, so I've decided to open up the patient and see whats going on.

I was not that surprised to find a nice chunk of my dog's hair and dust piled up between the heat sink and the cooling fan. As a result, heat wasn't getting transferred properly and thus the computer kept the cooling fan doing overtime == battery life plummets.

Here is how it looked before cleaning (apologize for the slight blur in the pictures):

And after I cleaned it up:

Here is my dog, her name is Layla:

And finally, I want to express my sincere thanks to insidemylaptop.com for their guide on how to disassemble an HP 530 notebook, It's an old model, I know, but it still carries me :-)

Has my cables provider's billing system been compromised?

2010-09-24T15:13:00.002+02:00

My cable provider (internet and telephony infrastructure) in Israel is a company called HOT. I get my invoices from their service into my mail, and this morning I got this email:

This email's title is in hebrew, translated it says: "A notification about a change in billing service username" (roughly) the sender seems to be HOT but in fact it is not, as you can see, the red arrow points to the real underlying email address: "newsletter@em-sender1.com", this is how it looks normally (green arrow):

Normally, links in emails coming from HOT billing service lead to https://mybills.hot.net.il/something, e.g (green arrow):

However, in the suspicious email the links looks very... err... suspicious :)
(red arrow again)

So this email is either a very unwise attempt to use some external email sending service or, and I stress the OR, it means someone is trying a phishing move. I find it hard to believe someone would try such a specific phishing email on a random bank of emails...

My only logical conjecture is: the sender had access to a list of HOT customers (business customer in my case), which is a very scary conjecture, one that I hope will be proven wrong...

UPDATE:

Further investigation reveals that em-sender*.com might be connected to a company called inwise.com. Hmmm... this mail might be legit after all...

Funny YouTube Internal Server Error message

2010-09-23T14:23:00.001+02:00

Chrome's new(?) invalid https certificate icon

2010-09-17T20:13:00.002+02:00

How cool is that:

Using Facebook Javascript SDK in your Blogger blog (Like button example)

2010-09-08T18:01:00.011+03:00

Before you go any further you must read (and implement) my post about open graph:

Teach your Blogger Blog to speak Facebook's open graph protocol

Open your blogger design interface and goto edit html and find the body opening tag (search page for <body). In another browser window open this reference url on facebook's developers site: http://developers.facebook.com/docs/reference/javascript/ copy the code there and paste it right after the body tag in your blogger template. The code snippet you just pasted should contain the following text: appId: 'your app id' (if it doesn't then facebook might have changed something and this post might not be relevant anymore).

If you properly followed the previous post (teach your blogger...) then you should have a Page on facebook for your blog by now, Go to it. We need the ID of that page, we can copy it from the address bar of our browser:

See the yellow marked number thats the ID of the page, copy it and paste it instead of your app id text (leave the single quotes in tact) in the code snippet we copy pasted from facebook. Save the template! :)

Time to add a like button to each post but first, make sure the Expand widget template checkbox is checked in your template editor:

I've decided to place the like button beneath the title of each post and at the end of it, the exact position in the template depends on your blogger's template, when you locate the desired spot, paste the following code in it:

<!-- facebook local post like button -->
     <b:if cond='data:post.link'>
       <fb:like expr:href='data:post.link' layout='button_count' show_faces='false' width='200'/>
     <b:else/>
        <b:if cond='data:post.url'>
       <fb:like expr:href='data:post.url' layout='button_count' show_faces='false' width='200'/>
        <b:else/>
       <fb:like expr:href='data:url' layout='button_count' show_faces='false' width='200'/>
        </b:if>
     </b:if>
<!-- facebook local post like button -->

And that should be it. If everything went right you should now see a like button on your blog, try it... and please try my button too ;-)

Using Blogger data tags inside script tags

2010-09-08T17:12:00.002+03:00

Template will look like this:

<script type='javascript'>
var url='<data:blog.url/>';
</script>

And the rendered result will look like this:

<script type="javascript">
var url='http://blog.yanivkessler.com/';
</script>

Concatenating text in blogger data tags

2010-09-08T17:08:00.001+03:00

I was messing around with my blogger template, testing the best way to integrate a facebook Like button into posts (this due to numerous demands to see how its done properly and not in a side bar).

One of the methods I tested required me to generate different ids for different posts and the most logical way to do so would be to use to post id somehow. I searched the reference on blogger support but couldn't find any example, so I looked inside some templates and I found an example. So in the template we type this:

<span expr:id='&quot;myId&quot; + data:post.id'></span>

Please note that I have to use encoded quotes to surround the text and concatenate using the plus sign. This html will be rendered as a result by blogger engine:

<span id='myId8712387612387612'></span>

Teach your Blogger Blog to speak Facebook's open graph protocol

2010-07-12T18:33:00.006+03:00

In your blog's control panel goto the Design tab and select Edit HTML. Find a tag called "<head>" (ctrl+f if you can't find it quickly) and add this code right after it:

<!-- Facebook open graph --> 

<b:if cond='data:blog.pageType == &quot;item&quot;'>
    <meta expr:content='&quot;the post: &quot; + data:blog.pageName' property='og:title'/> 
    <meta content='article' property='og:type'/> 
</b:if>

<b:if cond='data:blog.pageType == &quot;archive&quot;'>
    <meta expr:content='data:blog.pageName + &quot; posts&quot;' property='og:title'/> 
    <meta content='article' property='og:type'/> 
    <meta expr:content='data:blog.pageTitle' property='og:description'/> 
</b:if>

<b:if cond='data:blog.pageType == &quot;index&quot;'>
    <meta content='the blog' property='og:title'/> 
    <meta content='blog' property='og:type'/> 
    <meta content='Put your helmet on!' property='og:description'/> 
</b:if>

<meta expr:content='data:blog.url' property='og:url'/> 
<meta content='http://3.bp.blogspot.com/_XnhytjnfyaU/TBI7ItnIPII/AAAAAAAABJY/SJRWM5RHDgI/S1600-R/header.png' property='og:image'/> 
<meta content='625752324' property='fb:admins'/> 
<meta expr:content='data:blog.title' property='og:site_name'/> 

<!-- Facebook open graph -->

Here is a break down of whats going on here:
This code is specific for item (post) pages, it tells facebook that the title for this page should be The post: <post name here> and the graph object type is article (this tells facebook that the content is transient, see link to reference at the end of this post).

<b:if cond='data:blog.pageType == &quot;item&quot;'>
    <meta expr:content='&quot;the post: &quot; + data:blog.pageName' property='og:title'/> 
    <meta content='article' property='og:type'/> 
</b:if>

The result on the user's wall will look like this:

Next:
This code handles archive pages (like this one) and will tell facebook that the title should be <month year> posts e.g. December 2008 posts.

<b:if cond='data:blog.pageType == &quot;archive&quot;'>
    <meta expr:content='data:blog.pageName + &quot; posts&quot;' property='og:title'/> 
    <meta content='article' property='og:type'/> 
    <meta expr:content='data:blog.pageTitle' property='og:description'/> 
</b:if>

The result on the user's wall will look like this:

Next:
Code to handle data in our blog's index (homepage), this will tell facebook that the title is the blog and the type of the graph object is blog. I also specified a static description text: put your helmet!

<b:if cond='data:blog.pageType == &quot;index&quot;'>
    <meta content='the blog' property='og:title'/> 
    <meta content='blog' property='og:type'/> 
    <meta content='Put your helmet on!' property='og:description'/> 
</b:if>

The result on the user's wall will look like this:

Finally, we're telling facebook about some general stuff:
Here we wire the current page's url to the open graph protocol's url property:

<meta expr:content='data:blog.url' property='og:url'/>

The image facebook uses all around when displaying our graph object on facebook:

<meta content='http://3.bp.blogspot.com/_XnhytjnfyaU/TBI7ItnIPII/AAAAAAAABJY/SJRWM5RHDgI/S1600-R/header.png' property='og:image'/>

The user id (or ids) of the facebook profiles that administer this page (see how to find your user id here):

<meta content='625752324' property='fb:admins'/>

A title for the site:

<meta expr:content='data:blog.title' 
property='og:site_name'/>

Basically in places where we want a dynamic blogger property we use expr:<attribute>='<blogger data expression>' instead of simple html attributes like context="My title".

If you want to see how Facebook reads your open graph protocol metadata you can use Facebook's URL Linter.

Here you'll find the Open Graph Protocol's reference.

For more information, please see my post on how to use Facebook Javascript SDK from your blog and properly add a "like" button to your posts.

Also, check out some cool blogger books on amazon: Search Amazon.com for blogger

Another parent child relationship pitfall (jdo)

2010-06-23T02:08:00.001+03:00

Its a rookie's mistake but it stole an hour of my life, so at least I hope this will save someone else's time. I was making an experiment on AppEngine with big collections and I wrote these very simple parent and child classes to help in my test:

@PersistenceCapable
public class ParentWithBidiOwnedChildren {

 @Persistent(mappedBy="parent")
 private Set<ChildWithBidiOwningParent> children;

 public ParentWithBidiOwnedChildren() {
  children = new HashSet<ChildWithBidiOwningParent>();
 }

 @PrimaryKey
 @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
 public Key id;

 public void addNewChild() {
  children.add(new ChildWithBidiOwningParent(this));
 }

 public Set<ChildWithBidiOwningParent> getChildren() {
  return children;
 }
}

And child:

@PersistenceCapable
public class ChildWithBidiOwningParent { 
 
 @PrimaryKey 
 @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
 public Key id;
 
 @Persistent
 private final ParentWithBidiOwnedChildren parent;

 public ChildWithBidiOwningParent(ParentWithBidiOwnedChildren parent) {
  this.parent = parent;  
 }

 public ParentWithBidiOwnedChildren getParent() {
  return parent;
 }
}

In Eclipse IDE when you hit ctrl+1 you can quickly create a member field from a constructor parameter:

Eclipse generates a final field which is recommended and desirable in most cases:

What happens next, when you try to persist a parent, you get an exception:

javax.jdo.JDOUserException: Class "com.codeark.appengine.bigcollections.ParentWithBidiOwnedChildren" has collection field "children" and this has no mapping in the table for the element class "com.codeark.appengine.bigcollections.ChildWithBidiOwningParent" owner field "parent"

Immediately I started looking for an error in my annotations, but the smoking gun was that auto generated final keyword, so here is the correct child code:

@PersistenceCapable
public class ChildWithBidiOwningParent { 
 
 @PrimaryKey 
 @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
 public Key id;
 
 @Persistent
 private ParentWithBidiOwnedChildren parent;

 public ChildWithBidiOwningParent(ParentWithBidiOwnedChildren parent) {
  this.parent = parent;  
 }

 public ParentWithBidiOwnedChildren getParent() {
  return parent;
 }
}

That was a very unpleasent hour for me :-)

Blogger launches new template designer

2010-06-11T16:34:00.001+03:00

Looks slick...

Congrats !!!

Lightweight JDO Persistence Filter using Guice

2010-06-08T17:13:00.003+03:00

Here is a very lightweight and simple PersistenceFilter for your Guice powered webapps:

@Singleton
public class PersistenceFilter implements Filter {

 private final Provider<PersistenceManager> pmp;

 @Inject
 public PersistenceFilter(Provider<PersistenceManager> pmp) {
  this.pmp = pmp;
 }

 @Override
 public void destroy() {
 }

 @Override
 public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
  PersistenceManager pm = pmp.get();
  try {
   chain.doFilter(request, response);
  } finally {
   pm.close();
  }
 }

 @Override
 public void init(FilterConfig arg0) throws ServletException {
 }
}

This is no replacement for warp-persist and the soon to come guice persistence support, but look how simple it is, I love it! :-)

So how does this work? the "magic" is done by using Guice scoping, basically PersistenceManager is tied to the Request scope and all we have to do is close it at the end of the request. I'm going to show this in the context of an AppEngine application (cuz thats what I'm working on right now), so here is our web.xml:

<?xml version="1.0" encoding="utf-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
 version="2.5">

 <filter>
  <filter-name>guiceFilter</filter-name>
  <filter-class>com.google.inject.servlet.GuiceFilter</filter-class>
 </filter>

 <filter-mapping>
  <filter-name>guiceFilter</filter-name>
  <url-pattern>/*</url-pattern>
 </filter-mapping>

 <listener>
  <listener-class>com.codeark.persistencefilterexample.Bootstrap</listener-class>
 </listener>
</web-app>

Its an ordinary, run of the mill Guice powered webapp web.xml config file (see this post if you're using wicket, and why...)

The Bootstrap listener looks like this:

public final class Bootstrap extends GuiceServletContextListener {

 @Override
 protected Injector getInjector() {
  return buildInjector();
 }

 public Injector buildInjector() {  
  Injector infrastructure = Guice.createInjector(    
    new AppEngineModule(), 
    new PersistenceModule(), 
    new WebModule());

  return infrastructure;
 }
}

AppEngineModule handles the bindings of GAE specific services:

public class AppEngineModule extends AbstractModule {
 
 private static final PersistenceManagerFactory pmf = JDOHelper.getPersistenceManagerFactory("transactions-optional");
  
 public AppEngineModule() {  
 }

 @Override
 protected void configure() {
 }
 
 @Provides
 PersistenceManagerFactory providesPersistenceManagerFactory() {
  return pmf;
 }

 @Provides
 UserService providesUserService() {
  return UserServiceFactory.getUserService();
 }
 
 @Inject
 @Provides
 @SessionScoped
 User providesCurrentUser(UserService userService) {
  return userService.getCurrentUser();
 }
}

Please note the providesPersistenceManagerFactory() which localizes the use of static state to this module only. Additionally, diverging from the main topic of this post, take a look at providesCurrentUser(UserService userService) which simply allows you to Inject the current Google Account User (if one is logged in this session) anywhere in your code, its really handy.

Now comes the PersistenceModule:

public class PersistenceModule extends AbstractModule {
 
 public PersistenceModule() {  
 }

 @Override
 protected void configure() {
  bind(PersistenceManager.class).toProvider(PersistenceManagerProvider.class).in(RequestScoped.class);
  bind(DataService.class).to(DataServiceImpl.class); 
 } 
}

The most important line here is the first one where we bind PersistenceManager to the request scope. The provider follows:

public class PersistenceManagerProvider implements Provider<PersistenceManager> {

 private final PersistenceManagerFactory pmf;

 @Inject
 public PersistenceManagerProvider(PersistenceManagerFactory pmf) {
  this.pmf = pmf;  
 }

 @Override
 public PersistenceManager get() {
  return pmf.getPersistenceManager();
 }
}

I could have used a @Provides method in PersistenceModule instead, but that would force me to inject PersistenceManagerFactory into PersistenceModule and I like to avoid module injection where possible.

Last but not least, WebModule:

public class WebModule extends ServletModule {
 
 @Override
 protected void configureServlets() {
  filter("/*").through(PersistenceFilter.class);  
  serve("/test").with(TestServlet.class);  
 }   
}

It is important that PersistenceFilter will precede any other filters or servlets that need persistence (see Dispatch order in Guice documentation) otherwise you might end up with a closed persistence manager.

Finally, our test servlet which uses persistence via DataService:

@Singleton
public class TestServlet extends HttpServlet {

 private final DataService dataService;
 private final Provider<User> currentUser;

 @Inject
 public TestServlet(DataService dataService, Provider<User> currentUser) {
  this.dataService = dataService;
  this.currentUser = currentUser;
 }

 public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {

  resp.setContentType("text/plain");

  User current = currentUser.get();

  if (current == null) {
   resp.getWriter().println("You are not signed in to your google account, but Hello, world! anyways :-)");
  } else {
   resp.getWriter().println(String.format("Hello, %s", current.getNickname()));
   //records user and ip in datastore
   dataService.persist(new MyEntity(current, req.getRemoteAddr()));
  }
 }
}

The DataService implementation looks like this:

public final class DataServiceImpl implements DataService {
 
 private Provider<PersistenceManager> pmp;
 
 @Inject
 public DataServiceImpl(Provider<PersistenceManager> pmp) { 
  this.pmp = pmp; 
 }
 
 @Override
 public <T> T persist(T instance) {
  return pmp.get().makePersistent(instance);
 }

 @Override
 public void delete(Object instance) {
  pmp.get().deletePersistent(instance);
 } 
}

To summarize:

PersistenceManager is bound to a Request Scope, each request has its own PersistenceManager instance.
The PersistenceFilter is configured at the beginning of the request dispatch chain, its main role is to close the PersistenceManager at the end of each request.
Data Aware classes like DataServiceImpl use PersistenceManager by means of a Guice Provider (direct injection of PersistenceManager will impose a scope restriction on when we can instantiate classes that use it, so I think its best to avoid it)

As explained at the beginning of the post, this implementation is good for prototyping and small projects, for large / complex projects I'd go with a more solid, tested and much more capable framework (like warp-persist and guice-persist when it comes out)

The source is available in the form of an eclipse project here:

https://codeark.com/svn/persistence.filter.example/trunk/

You will need Google AppEngine Eclipse plugin to make it work.

Writing unit tests for Guice and Wicket

2010-06-01T20:46:00.005+03:00

There are excellent frameworks out there for bringing the Guice power into your JUnit tests, like AtUnit or GuiceBerry, however, for the sake of simplicity, this post builds upon a simple Test Runner class described in another post written in 2008 by Gili Tzabari about Guice and JUnit4 integration.

Here is a very simple MyGuiceTestRunner implementation:

public class MyGuiceTestRunner extends GuiceTestRunner {
 public MyGuiceTestRunner(Class<?> classToRun) throws InitializationError {
  super(classToRun, new WebModule(), new MyModule(), new HibernateModule());
 }
}

And here is an abstract wicket test to ease our work later:

@RunWith(MyGuiceTestRunner.class)
public class AbstractWicketTest {
 
 private final WicketTester wicketTester;
 
 protected final WicketTester getWicketTester() {
  return wicketTester;
 }

 public AbstractWicketTest(Injector injector) {
  wicketTester = new WicketTester();
  WebApplication app = wicketTester.getApplication();
  app.addComponentInstantiationListener(new GuiceComponentInjector(app, injector));
 }
}

Some points of intrest in this implementation:

Class is annotated with @RunWith, this tells JUnit to use MyGuiceTestRunner to run this test (and subclasses too).
In the constructor we create a WicketTester which in turn will create a dummy wicket web application for us (BaseWicketTester.DummyWebApplication is the exact type). If we need a custom application we could simply use other WicketTester constructors that take an Application instance and use it instead of the inner dummy one.
Once a WicketTester instance was created, we add attach a GuiceComponentInjector just like we would in a normal guicey wicket web application.

In a typical test subclass of AbstractWicketTest we get a reference to the injector using constructor injection (remember this test is injectable because it is being run by MyGuiceTestRunner):

public class SampleWicketTest extends AbstractWicketTest {
 
 @Inject
 public SampleWicketTest(Injector injector) {
  super(injector);
 }

 @Test
 public void test() {
  WicketTester wicketTester = getWicketTester();
  wicketTester.startPage(TestPage.class);
  wicketTester.assertRenderedPage(TestPage.class);
  wicketTester.assertLabel("meow", "Testing 1 2 3");
 }
}

For the sake of completeness, here is the code for the test page itself (html markup omitted):

public class TestPage extends WebPage { 
 
 @Inject private IService service;
 
 public TestPage() {
  add(new Label("meow", "Testing 1 2 3"));
  service.doSomething();
 } 
}

Thats it, you are now free to write Guice powered tests for your Guicey Wicket pages.

Enjoy :-)

Wicket and Guice integration: an alternate route...

2010-05-26T04:49:00.020+03:00

This post details a slightly different way of integrating Apache Wicket and Google Guice.

Many posts, reference docs and demos I've seen on the Internet so far, do not employ one of my most favorite features in Guice: the ServletModule to configure Wicket's filter. I really like this feature because I really don't like configuration files and the Web Descriptor (a.k.a web.xml) file is one of the most disliked of them all :) but Thanks to Guice this file's annoyance goes almost unnoticed.

So just to make it clear, the purpose of this integration is to bypass wicket's filter configuration in web.xml and put it in code instead.

Before we start here are several links to posts and reference docs about Wicket and Guice integration that are more common (but do use web.xml to config wicket):

Wicket Guice GuiceWebApplicationFactory javadoc
Alastair Maw’s blog - Wicket gets guicy
Wicket examples - Guice
Atomic Gamer dev blog - Wicket, Guice and Warp-Persist

We start with the web.xml file:

<?xml version="1.0" encoding="utf-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
 version="2.5">

 <filter>
  <filter-name>guiceFilter</filter-name>
  <filter-class>com.google.inject.servlet.GuiceFilter</filter-class>
 </filter>

 <filter-mapping>
  <filter-name>guiceFilter</filter-name>
  <url-pattern>/*</url-pattern>
 </filter-mapping>

 <listener>
  <listener-class>com.codeark.wicketguicealt.Bootstrap</listener-class>
 </listener> 
</web-app>

This web.xml only configures Guice filter and a GuiceServletContextListener as per the instructions here.

The Bootstrap class loads our modules:

public final class Bootstrap extends GuiceServletContextListener { 
 @Override
 protected Injector getInjector() {  
  return Guice.createInjector(new MyModule(), new WebModule());
 } 
}

The binding and configuration of Wicket happens in WebModule (a subclass of ServletModule):

public class WebModule extends ServletModule {
 
 @Override
 protected void configureServlets() {
  bind(WebApplication.class).toProvider(WicketGuiceAppProvider.class);
  
  // avoids "Error initializing WicketFilter - you have no <filter-mapping> element..." 
  // IllegalArgumentException
  Map<String, String> params = new HashMap<String, String>();  
  params.put(WicketFilter.FILTER_MAPPING_PARAM, "/*");
  
  filter("/*").through(WicketGuiceFilter.class, params);
 }
}

In the first line of configureServlets() we bind WebApplication to a provider, this provider will be our real application factory and will do all the work instead of GuiceWebApplicationFactory.

The GuiceWebApplicationFactory implementation requires that the injector will be stashed in the Servlet Context or that modules will be listed in the web.xml in an init-param like this:

<init-param>
        <param-name>module</param-name>
        <param-value>com.company.MyModule,com.company.MyOtherModule</param-value>
</init-param>

I think both options contradicts the real notion of Guice: "Rather than using an external XML file for configuration, Guice modules are written using regular Java code. Java is familiar, works with your IDE, and survives refactoring" and therefor I opted not to use GuiceWebApplicationFactory. Here is the provider we will use:

public class WicketGuiceAppProvider implements Provider<WebApplication> {
 
 private final Injector injector;

 @Inject
 public WicketGuiceAppProvider(Injector injector) {
  this.injector = injector;  
 }
 
 @Override
 public WebApplication get() {
  WicketGuiceApp app = new WicketGuiceApp(injector);  
  return app;
 }
}

It would be awesome if we could call addComponentInstantiationListener(new GuiceComponentInjector(app, injector)) here instead of passing the injector in the constructor (on injecting it) but GuiceComponentInjector uses InjectorHolder in its constructor:

public GuiceComponentInjector(Application app, Injector injector)
{
 app.setMetaData(GuiceInjectorHolder.INJECTOR_KEY, new GuiceInjectorHolder(injector));
 InjectorHolder.setInjector(this);
}

and InjectorHolder has a dependency on the application instance being tied to the current thread (Application.get() uses ThreadLocal):

public static void setInjector(ConfigurableInjector newInjector)
{
 Application application = Application.get();
 application.setMetaData(INJECTOR_KEY, newInjector);
}

Consequently, we can only call addComponentInstantiationListener() after Application.set() is called and the best place to do so is in the init() method of our WebApplication implementation. we could use Application.set() ourselves (tried that and it works fine) but the scary warnings in the javadoc are scary :-), so here is our WicketGuiceApp class with its init() method:

public class WicketGuiceApp extends WebApplication {
 
 private transient Injector injector;
 
 public WicketGuiceApp(Injector injector) {
  this.injector = injector;  
 }
 
 @Override
 protected void init() {  
  addComponentInstantiationListener(new GuiceComponentInjector(this, injector));
 }

 @Override
 public Class<? extends Page> getHomePage() {
  return HomePage.class;
 }
}

Please note that I've marked the Injector as transient. Under the hood, GuiceComponentInjector will handle the Injector's reference serialization and deserialization.

Back to WebModule, the second important thing we do in configureServlets() is to configure the Wicket filter and filter mapping. We are using our own WicketFilter subclass called WicketGuiceFilter in order to utilize our provider and wire it into wicket's IWebApplicationFactory:

@Singleton
public class WicketGuiceFilter extends WicketFilter {

 @Inject private Provider<WebApplication> appsProvider;
 
 @Override
 protected IWebApplicationFactory getApplicationFactory() {
  return new IWebApplicationFactory() {   
   @Override
   public WebApplication createApplication(WicketFilter filter) {    
    return appsProvider.get();
   }
  };
 } 
}

The reason I chose to subclass WicketFilter instead of doing this inside configureServlets():

Map<String, String> params = new HashMap<String, String>();
 
 params.put(WicketFilter.APP_FACT_PARAM, WicketGuiceAppFactory.class.getName());
 filter("/*").through(WicketFilter.class, params);

Is that WicketFilter instantiates the factory via reflection and the prevents Guice from doing its work.

This concludes our integration, would love to hear any comments.

You can download just the full source of this post and web.xml here

OR

You can download a full eclipse dynamic web project with dependencies included, you will need to import it to your workspace and reconfigure a servlet container runtime (such as apache tomcat) before you can build.

OR

Get the above eclipse project via svn or simply browse the code for your convenience here:
https://www.codeark.com/svn/wicket.guice.alt/trunk
This repository is read only for anonymous access.

HOWTO: Open a webpage programmatically in an android java application

2010-05-13T21:37:00.006+03:00

Using an intent like this:

Intent intent = new Intent("android.intent.action.VIEW", Uri.parse("http://www.codeark.com"));

try {
 this.startActivity(intent);
} catch (ActivityNotFoundException ex) {
 // do something about the exception, or not ...
}

"this" is the Context.

more info here: Context.startActivity()

Google auto complete does computation?

2010-05-05T04:29:00.001+03:00

only noticed it now:

nice!

Wicket vs. GWT

2010-04-02T02:36:00.001+03:00

A very interesting and in depth comparison between the two:

http://ptrthomas.wordpress.com/2008/09/04/wicket-and-gwt-compared-with-code/

PHP on Windows - WHY?

2010-02-04T21:40:00.001+02:00

Check out this short overview by Shai Raiten:

http://blogs.microsoft.co.il/blogs/shair/archive/2010/01/30/php-on-windows-summary.aspx

DiskDigger

2010-01-30T11:47:00.003+02:00

It was a wonderful Saturday morning. I rose up and started my morning really slowly, was staying at a friend's house. At some point I took my laptop, plugged in my USB stick and prepared to do some useful things with my item.

USB is not responding, oh well that happens every now and then, lets replug, still not working... A small alarm indicator went in my head. Lets try the other port, computer recognize the stick, the free/used space match, but... OH MY GOD, NO FILES!!!

*Sigh* just two months ago I lost a 250g disk to a hardware malfunction... I've decided to run chkdsk, and indeed, errors were found, but there was insufficient disk space on the stick for chkdsk do finish his thing (and a good thing that!). It was a mistake to use chkdsk, I should have used a recovery software right away.

The file system on the stick went caput :-(

From google, I got to checking The Free Country, an excellent source of free software. After trying several utilities from the Data Recovery section, I found this excellent utility: DiskDigger

Unfortunately at this point all I was left to work with was scattered blocks of that on the hard drive, so simple undelete procedures didn't work. DiskDigger however, managed to recover most of my important files, the docs and pictures especially.

Now I'm left with the annoying task of sorting through the unnamed files... This really ruined my Saturday.

Blah...

Parent/Child Hibernate pitfall

2010-01-20T04:49:00.013+02:00

Lets say we have these two interfaces:

package com.codeark.parentchild;

import java.util.Set;

public interface Parent {
Set<Child> getChildren();
}

And

package com.codeark.parentchild;

public interface Child {
Parent getParent();
}

And here are their implementations, annotated for persistence:

package com.codeark.parentchild;

import java.util.HashSet;
import java.util.Set;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;

@Entity
@Table(name="parents")
public class ParentImpl implements Parent {

private Set<Child> children;
private Long id;

public ParentImpl() {
this.children = new HashSet<Child>();
}

@Override
@OneToMany(targetEntity=ChildImpl.class, mappedBy="parent", cascade=CascadeType.ALL)
public Set<Child> getChildren() {
return children;
}

public void setChildren(Set<Child> children) {
this.children = children;
}

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}
}

And the child implementation:

package com.codeark.parentchild;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Table;

@Entity
@Table(name="children")
public class ChildImpl implements Child {

private Parent parent;
private Long id;

public ChildImpl() {

}

@Override
@ManyToOne(targetEntity=ParentImpl.class)
public Parent getParent() {
return parent;
}

public void setParent(Parent parent) {
this.parent = parent;
}

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}
}

So, where is the pitfall? Well, there are probably a few lying about, but the one I ran into will become apparent shortly. First, consider this code snippet:

Parent p = new ParentImpl();
Child c = new ChildImpl();

p.getChildren().add(c);
((ChildImpl)c).setParent(p);

// persist to database
DAOFactory.getParentDAO().persist(p);

Now, another programmer joined the show, and decided to have his own Child implementation:

package com.codeark.parentchild;

public class AnotherChildImpl implements Child {

private Parent parent;

public AnotherChildImpl() {

}

protected void someOtherNewMethods() {

}

@Override
public Parent getParent() {
return parent;
}

public void setParent(Parent p) {
this.parent = p;
}
}

A perfectly legal implementation, lets have a look at another code snippet:

Parent p = new ParentImpl();
Child c = new ChildImpl();
Child c1 = new AnotherChildImpl();

p.getChildren().add(c);
p.getChildren().add(c1);
((ChildImpl)c).setParent(p);
((AnotherChildImpl)c1).setParent(p);

// persist to database
DAOFactory.getParentDAO().persist(p);

What do you think will happen now? This code will compile, but during runtime Hibernate will hit us with an IllegalArgumentException in class: com.codeark.parentchild.ChildImpl, getter method of property: id

org.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of com.codeark.parentchild.ChildImpl.id...

This is a result of me telling hibernate to expect a ChildImpl (targetEntity) while in practice that collection contained AnotherChildImpl class, which hibernate knows nothing about.

Why is this so bad?

This exception will not occur until the program tries to persist a ParentImpl with an AnotherChildImpl bomb waiting to explode in its children collection. That event can happen far into the (runtime) future. Although I doubt such a bug will make it to production if you have decent integration and QA, its still within the realm of possibilities; it would be best if we do what ever we can to prevent that eventuality.

Here is what I did to prevent this...

First I changed the parent Interface:

package com.codeark.parentchild;

import java.util.Set;

public interface Parent {
Set<? extends Child> getChildren();
}

Note that our children collection is now of an unknown type bounded by Child, instead of just Child.

Then I changed ParentImpl:

package com.codeark.parentchild;

import java.util.HashSet;
import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;

@Entity
@Table(name="parents")
public final class ParentImpl implements Parent {

private Set<ChildImpl> children;
private Long id;

public ParentImpl() {
this.children = new HashSet<ChildImpl>();
}

@Override
@OneToMany(mappedBy="parent", cascade=CascadeType.ALL)
public Set<ChildImpl> getChildren() {
return children;
}

public void setChildren(Set<ChildImpl> children) {
this.children = children;
}

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}
}

Our HashSet collection is now of ChildImpl type instead of just Child, I've changed that throughout the class's internals and external API. Our class still complies with Parent's contract, since we've changed Parent.getChildren() from Set<Child> to Set<? extends Child>

As an added bonus, we no longer need the targetEntity=ChildImpl.class annotation for ParentImpl.getChildren().

Last small caveat, I've marked the class as "final" since subclassing it without proper annotations/mapping might expose us to similar problems.

Another important change; in ChildImpl class:

package com.codeark.parentchild;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Table;

@Entity
@Table(name="children")
public final class ChildImpl implements Child {

private ParentImpl parent;
private Long id;

public ChildImpl() {

}

@Override
@ManyToOne
public ParentImpl getParent() {
return parent;
}

public void setParent(ParentImpl parent) {
this.parent = parent;
}

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}
}

All the Parent references were changed to ParentImpl, so I wouldn't face a similar problem if someone tries to add a non persistent parent to ChildImpl.

Lets look at our buggy code again:

ParentImpl p = new ParentImpl();
ChildImpl c = new ChildImpl();
Child c1 = new AnotherChildImpl();

p.getChildren().add(c);
p.getChildren().add(c1);  // A Compile time error here!

Now the "other" programmer will get a compile time error, while trying to add his new (and improved) class to your parent Implementation, and the world is a slightly better place now.

Yet another magnificent blog

2009-12-27T01:46:00.002+02:00

http://acko.net/blog/

Really cool design

Tomcat and Wicket's unruly logging

2009-11-09T17:00:00.016+02:00

Note: if you want the solution just skip to the end...

Like many before me, I too ran into the problem where wicket was spamming log message into "catalina.out".

At first, naively, I tried to change my log4.properties file, but alas, wicket seemed intent on ignoring these changes. Following that failure, I tried changing Tomcat's logging.properties but that didn't seem to effect wicket's either.

Frustrated and naturally lazy I turned over to Google, the almighty human knowledge repository. If you know what to feed in that little search box, Google can save you loads of time and also the effort of actually understanding what is it you are doing (so basically good googling skills are essential to the indolent).

In this case however, this wonderful "googelazy" phenomenon was in fact hindering my efforts. Once I realized my salvation will not be so easy, I went on to read the documents of the logging lib used by Wicket: slf4j.

After perusing the documentation for a while I ran into this:

So I've decided to check my classpath and see which implementation I'm using. It turns out I was using slf4j-simple.jar which outputs everything to System.err:

slf4j-simple-1.5.9.RC1.jar

Binding for Simple implementation, which outputs all events to System.err. Only messages of level INFO and higher are printed. This binding may be useful in the context of small applications.

The solution was simple after that, replace the slf4j-simple.jar with something else, in my case it was the slf4j-log4j12.jar

Sub conclusion: if the answer was googlable it would have poped up straight away, next time I should rtfm

Thank you, diskinternals.com zip repair!

2009-10-22T00:36:00.002+02:00

For saving my 1.6 gigs zip codebase file.

http://www.diskinternals.com/zip-repair/

god bless you! :-)

Dub FX

2009-05-07T22:31:00.003+03:00

This human beatbox artist is just amazing. His music is really unique and refreshing!

Make some noise :-)

http://www.youtube.com/watch?v=OEPEleJVjOo

http://www.youtube.com/watch?v=WhBoR_tgXCI

http://www.youtube.com/watch?v=8F6EoMdn95E

Checkout his website too: http://www.dubfx.net/

A life saver: Privacy policy generator

2009-04-16T07:25:00.003+03:00

http://www.dmaresponsibility.org/PPG/

My company's new website

2009-03-25T20:59:00.003+02:00

http://www.codeark.com

comments will be happily accepted! :)

(even negative ones, just be gentle...)

Wicket, Ajax, UTF-8 and Tomcat connectors

2009-03-14T02:34:00.007+02:00

While working on one of my backoffice applications, I stumbled upon a problem where hebrew text would turn into encoded gibberish after inputing it into an ajax editable control (like AjaxEditableLabel or AjaxEditableMultiLineLabel).

After looking around in wicket's ajax debug console I found out that the problem was on the server side, quick googling action turned out the following possible problem/solution, the tomcat connector's declaration is missing a URIEncoding attribute:

<Connector port="8080" maxHttpHeaderSize="8192"
     maxThreads="150" minSpareThreads="25" maxSpareThreads="75"
     enableLookups="false" redirectPort="8443" acceptCount="100"
     connectionTimeout="20000" disableUploadTimeout="true"     
     URIEncoding="UTF-8"/>

Original post here

I was very happy its a simple solution and was almost 100% this would solve the problem, However, it didn't do the trick! why?!

Well, My tomcat sits behind an apache httpd server (proxy), because I like to complicate things sometimes (and because my server is a hybrid serving php, java, python perl and so on). Now, apache and tomcat communicate via AJP protocol, so the URIEncoding attribute should be present for that connector declaration as well:

<Connector
     server="Apache PowerCore"
     port="8009"
     protocol="AJP/1.3"
     URIEncoding="UTF-8" />

For the sake of computer voodoo, I left the encoding attribute in the http connector as well. Computer voodoo is a powerful thing :)

Extracting flv video files from Metacafe.com

2009-01-06T03:05:00.010+02:00

Metacafe.com, another excellent content provider on the net. The people at Metacafe.com made a sincere effort, hiding their flv files, so this actually took 30 minutes or so.

Now, for the method itself, we'll start with a classical video page at Metacafe (a real funny one too):

http://www.metacafe.com/watch/1185371/hidden_camera_sex_tape_by_liv_films/

Searching the page's source for the almighty string "flv" reveals the follow piece of literature inside:


$('FlashMsg').removeClass('Hidden');
var so = playerSwfObjectInstace = new SWFObject("http://s.mcstatic.com/Flash/vp/PortalVideoPlayer_6.1.0.3.swf", "fpObj", "100%", "100%", "8");

so.addParam("flashvars", '... lots of vars here, one we are interested in mediaUrl ...');

so.addParam("wmode", "transparent");
so.addParam("AllowScriptAccess", "always");
so.addParam("allowFullScreen", "true");
so.addParam("quality", "high");
so.useExpressInstall("http://s.mcstatic.com/Flash/expressinstall.swf");
var fsManager = new FlashFS('FlashObj','FlashWrap');

... more stuff down here...

In the midst of that big chunk of javscript we will find this:

mediaURL=http%3A%2F%2Fv.mccont.com%2FItemFiles%2F%255BFrom%2520www.metacafe.com%255D%25201185371.6511758.11.flv&gdaKey=1231211887_23b55c6077f00398853fe903f8cd9905

if you try to just decode it, and put it in your browser you will get an error... hmm... well to make a long story short, and without boring you with too much technical details, after you decode this url into this:

http://v.mccont.com/ItemFiles/%5BFrom%20www.metacafe.com%5D%201185371.6511758.11.flv&gdaKey=1231211887_23b55c6077f00398853fe903f8cd9905

replace the bolded text with this: ?__gda__ and it works.

Final url will look like this:

http://v.mccont.com/ItemFiles/%5BFrom%20www.metacafe.com%5D%201185371.6511758.11.flv?__gda__=1231211887_23b55c6077f00398853fe903f8cd9905

Thats it, if this looks a bit too much you may wanna try this toolbar.

Extracting flv video files behind Last.fm

2009-01-01T21:31:00.010+02:00

This would be the third post in what seems to be an emerging "series" of posts portraying various methods of getting the flv resource files behind various popular video/media online hosting thinggies.

Last.fm is a wonderful music service (go check it out!) that hosts a lot of media and ... bla bla bla... go check the about section there if you want more details.

Anyways, after checking out the source code for a typical video page on Last.fm I didn't find any obvious leads as to where they get they store their flv files. Also, Due to the late hour in which I was undertaking this fabulous activity, I've gotten lazy and decided to just turn on one of god's better gifts to the cyberworld called fiddler.

I picked a random page:

http://www.last.fm/music/The+Police/+videos/12005751 - The Police, King of pain :)

Switching to fiddler's session trace, search for the word "flv" and voilà:

"One session contained flv" Says the sign, couldn't be easier. Quickly copying the complete url from fiddler (right click + "copy > just url" or just hit ctrl + u):

http://userserve-ak.last.fm/serve/flv/12005751.flv?1221640857

What is the number after the question mark, you ask? I have no idea, I just elegantly ignored it and pasted the following url in the browser:

http://userserve-ak.last.fm/serve/flv/12005751.flv

And was rewarded with the flv file download dialog.

So how do we do this without fiddler? simple, now that we know what to look for, we can clearly see that the flv file name is the id that appears on the video's page:

http://www.last.fm/music/The+Police/+videos/12005751
http://userserve-ak.last.fm/serve/flv/12005751.flv

That's it, job's done.

Again after you download the flv, if you want to convert it to another format you might want to consider using this this splendid piece of sponsored software here

Addition to this post:

To download the videos that appear in urls of the form:

http://www.last.fm/videos / http://www.last.fm/videos/+tag/something

View the source of the url and look for this:


<noscript>
<object type="application/x-shockwave-flash" data="http://cdn.last.fm/videoplayer/l/11/VideoPlayer.swf" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=9,0,0,0"
        id="lfmEmbed_50_16202025_1334568063"
        width="450" height="373">
    <param name="movie" value="http://cdn.last.fm/videoplayer/l/11/VideoPlayer.swf" />
    <param name="flashvars" value="title=Human&amp;uniqueName=16202025&amp;albumArt=http%3A%2F%2Fcdn.last.fm%2Fdepth%2Fcatalogue%2Fnoimage%2Fnocover_flashplayer.png&amp;duration=259&amp;image=http%3A%2F%2Fuserserve-ak.last.fm%2Fserve%2Fimage%3A320%2F16202025.jpg&amp;FSSupport=true&amp;creator=The+Killers" />
    <param name="allowScriptAccess" value="always" />
    <param name="allowNetworking" value="all" />
    <param name="allowFullScreen" value="true" />
    <param name="quality" value="high" />
    <param name="bgcolor" value="000000" />
    <param name="wmode" value="opaque" />
    <param name="menu" value="false" />
</object></noscript>
</div>

uniqueName=16202025 contains the Id we need to feed to:

http://userserve-ak.last.fm/serve/flv/12005751.flv

Pour your own pint

2009-01-01T14:41:00.003+02:00

Just had to share with you this small bit of information a friend has told me about, last night he along with 19 other people booked a table at a bar in Cork City, Ireland, where you get a table with your own personal beer tap(s)! How awesome is that ?!

The special taps measure how much beer you pour, so you can pay accordingly later...

Check it out: Soho bar website

Extracting the flv file behind a MySpace.com video

2008-12-30T03:10:00.008+02:00

Took me a few minutes to find this on the web, so here it is again, mostly for me, but maybe for you too.

Providing we have the following MySpace.com video page:
http://vids.myspace.com/index.cfm?fuseaction=vids.individual&videoid=45134031

We extract the Video Id, which is 45134031 and then we feed it to MySpace RSS service:
http://mediaservices.myspace.com/services/rss.ashx?type=video&mediaID=45134031

If you check out the source of the result, our prize lies within:


<rss version="2.0" xmlns:media="http://search.yahoo.com/mrss" xmlns:myspace="http://myspace.com/"> 
  <channel> 
    <title>MySpace</title> 
    <description>MySpace</description> 
    <link>http://myspace.com/192982080</link> 
    <lastBuildDate>Mon, 29 Dec 2008 16:26:41 GMT</lastBuildDate> 
    <docs>http://myspace.com</docs> 
    <generator>CHA1mwebnet1246</generator> 
    <myspace:friendID>192982080</myspace:friendID> 
    <item> 
      <title>VIMBY - Novato Skatepark</title> 
      <pubDate>Mon, 29 Dec 2008 16:26:41 GMT</pubDate> 
      <media:thumbnail url="http://d4.ac-videos.myspacecdn.com/videos02/50/thumb0_afc9f68733bc87a1b7eb4dc9ec9a1bc7.jpg" /> 
      <media:content url="http://cache01-videos02.myspacecdn.com/50/vid_afc9f68733bc87a1b7eb4dc9ec9a1bc7.flv" type="video/x-flv" medium="video" duration="220" /> 
      <myspace:mediaID>45134031</myspace:mediaID> 
      <myspace:mediaSource>Video</myspace:mediaSource> 
      <myspace:itemID>45134031</myspace:itemID> 
      <myspace:itemType>Video</myspace:itemType> 
      <myspace:friendID>192982080</myspace:friendID> 
    </item> 
  </channel> 
</rss>

The xml element at line 14 "<media:content>" has a url attribute that contains a direct link to the flv file:
http://cache01-videos02.myspacecdn.com/50/vid_afc9f68733bc87a1b7eb4dc9ec9a1bc7.flv

There you go, you can now go ahead and download the flv and perhaps convert it to other video formats using this splendid piece of sponsored software here.

This works!

2008-12-27T11:14:00.001+02:00

Here is a funny java code snippet for the hebrew speakers among us, this actually compiles:


package com.codeark.rnd;

public class הקלאס {

 private static String יניב = "123123";
  
 public static void מתודה(String משתנה) {
  System.out.println(משתנה);
 }

 /**
  * @param args
  */
 public static void main(String[] args) {
  System.out.println(יניב);
  מתודה("asdasd");
 }

}

Funny :)

p.s. the static member is named יניב and its value is "123123"

Click Dating

2008-01-22T02:10:00.000+02:00

A controversial child in a long succession line of "X dating".

We've seen many of them around over the years: Blind dating, Video dating, Speed dating and so on and so forth.

What is Click Dating you ask ?

Click Dating is the term I give to all of those (mostly) facebook applications, where you sit like a mouse in a factory and click yes or no on portrait photos of the (sometimes :P ) opposite sex.

Its a new kind of statistical dating... you click 100 times, you might be getting between 1 to 10 replies from which 0.1 to 1 might actually yield any result. Actually, come to think about it, its very much like Internet advertising. You can definitely apply terms like Conversion Rate and even Cost Per Click... (just be imaginative with the latter :P )

So what happened to good old "Mommy and daddy met because daddy ran her over with his bicycle... and the rest is history" ?

I mean what would you tell your children in this case ? "Mommy and Daddy met after 10000000 clicks on Flirtable" ???

I admit I have joined the mice community and I did had my share of "conversions" from this, but call me a hopeless romantic, I'm still hoping that meeting my future second half would be much more similar to some classic movie scene than to an Internet banner statistical report.

Y

P.S. I wonder what the next X Dating will be.... if you can answer this one, its worth a lot of $$$ :D