A stupid hack to open short urls blocked by proxy via Launchy 4:57 AM

This script will be useful when short urls are blocked by a proxy within a network.

For example:

Lets say the link to an article or blog on the web is this:

LongUrl : http://something.com/somethingelse

Your friend reads the above article and mails the link to you in its shortened form:

ShortUrl : http://bit.ly/s1 or http://t.co/se1

Now when you are on a company network or a protected network, there is a good chance that bit.ly or t.co services are blocked by the proxy though the original site itself (something.com in this case) might not be blocked.

For such cases this silly vbscript can be handy. It basically talks to a longurl.org which lengthens the shortened url and opens it up on the browser.

lurl.vbs

set ws = CreateObject("WScript.Shell")

siteUrl = "http://longurl.org/expand?url=" & Wscript.Arguments.Named("u")

Dim objHttp

Set objHttp = CreateObject("Msxml2.ServerXMLHTTP")

objHttp.Open "GET", siteUrl, False

objHttp.Send

page = objHttp.ResponseText

Set objHttp = Nothing

longUrl = Split(Split(page,"Long URL:")(1),"""")(1)

ws.Run(longUrl)

I have saved the above lurl.vbs file under C:\Temp\Scripts.

From command prompt, running the below command will open up the link in the browser.

lurl /u:your-short-url        

                          

Further more, you can even configure it via the Launchy Runner plugin which makes it more fun.

                                   

Within launchy, typing lurl (tab) followed by site's short url will launch the site directly.

                                 

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Design Patterns: Factory Method Pattern 5:34 AM

/**
* A simple implementation of Factory Method Pattern
* using a real time CricketPlayer example
*/


//Base
public interface CricketPlayer{
    public String play();
}


//Subclass
class Bowler implements CricketPlayer{
    public String  play (){
        return "takes a wicket";
    }
}


//Subclass
class Batsman implements CricketPlayer{
    public String  play (){
        return "hits a six";
    }
}


//Factory class - contains the logic of instatiating players
public class CricketPlayerFactory{
    CricketPlayer player;
   
    public CricketPlayer getPlayerWho(String does){
        if(does.equals("bats"))
            player = new Batsman();
        else if(does.equals("bowls"))
            player = new Bowler();
        return player;              
    }
}


//Factory method implementation
public class FactoryImplementation{
    public static void main(String args){
        //create a factory
        CricketPlayerFactory factory = new CricketPlayerFactory();
        //ask factory to instantiate the player
        CricketPlayer player = factory.getPlayerWho("bats");
        //use the player
        System.out.prinln(player. play ());
    }
}

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Design Patterns: Singleton Pattern 5:10 AM

/**
* A simple Implementation of a singleton
*/
class MySingleton{
   
    static MySingleton singletonInstance;
   
   //****** instantiation ******


    static MySingleton getInstance(){
        if(singletonInstance == null)
            singletonInstance = new MySingleton();
        return singletonInstance;
    }
   
    private MySingleton(){
        //cannot be called public with new
    }


   //****** logic ******   
    ....
    ....
}


MySingleton.getInstance();


FYI, Points to remember

• Singletons are bad. 
• They are just glorified statics and hence against OOP principles. 
• They should be rarely used. A classic example: for logging purposes.
• Singletons are hard to unit test.
• Also bad because it is NEVER a good practice to mix instantiation and logic in a single class. 

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How to know HBOOT version and S-ON or S-OFF on HTC phones 4:09 AM

• Switch off the mobile completely.
• Hold the volume down button and simultaneously click the power-on button. This will login to the boot menu and display details like this:
  
  BUZZ PVT SHIP S-ON
  
  HBOOT-1.01.0002
  MICROP-0622
  TOUCH PANEL-ATMELC03_16ac
  RADIO-3.35.20.10
  Dec  2 2010, 17:14:26
  
  

  The first line displays the security flag status. For being able to play around with sudo root access on HTC phones the flag must be turned off (shows S-OFF if turned off). 
• Click power off button and next hold the volume down button to reboot again into normal menu. 

To be continued.. 

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Currying in Groovy 2:54 AM

Currying is a process of transforming a function of n arguments into n partial functions of one argument each.

Although I was acquainted with the math part of it. I found it hard to implement it in code. I
couldn't help but posting Tim Yate's sample snippet to my question on SO about a simple implementation for currying in groovy.

def greet = { greeting, person -> "$greeting $person" }


// This takes a closure and a default parameter
// And returns another closure that only requires the
// missing parameter
def currier = { fn, param ->
  { person1 ->
     fn( param, person1 )
  }
}


// We can then call our currying closure
def hi = currier( greet, 'Hi' )


// And test it out
hi( 'Vamsi' )

Here's an other pointer for doing functional programming in groovy. 

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Setting up Conky & Lua-Widgets 3:41 AM

Installing Conky-Lua widget/theme on Ubuntu

1) Install conky and conky-all from Ubuntu Software Center or via apt-get on terminal.

2) Unzip the contents of the tar.gz or zip of Conky/Lua theme submitted by the developer into some folder named Scripts.

Most importantly, the unzipped file will have a conky text file and a .lua file in it.

3) Ensure Nautilus Browser -> View -> Show hidden files option is enabled and create a hidden folder in your /home/Your_Username directory with the name .conky

4) Within the Scripts folder, search for file with .lua extension. This file contains the widget script. Copy the .lua file into the .conky folder.

5) Rename the left over text file in the Scripts folder to a hidden file named .conkyrc and place it in /home/Your_Username directory.


6) Open the .conkyrc file in gedit and edit the portion of the .conkyrc file which refers to the  widget location path i.e the .lua script path. In this case should point to

/home/Your_Username/.conky/someWidgetScript.lua

On terminal run command

conky

which will start the Conky theme/widget.


Installing Multiple Conky-Lua widget/themes on Ubuntu

By default, Running the conky command will invoke the .conkyrc text file at /home/Your_Username location and checks for lua scripts placed in the .conky folder.

In case of setting up multiple widgets you need to have multiple conky text files and multiple lua scripts.

Place all the .lua files in the .conky folder in the /home/Your_Username directory.

Let the text files remain in the Scripts folder but ensure that the configuration path in them points to their corresponding .lua scripts in the .conky folder. (as shown in step 6 above)

In terminal, run

conky -c /home/Your_Username/Scripts/ConkyTextFileScript1
conky -c /home/Your_Username/Scripts/ConkyTextFileScript2
conky -c /home/Your_Username/Scripts/ConkyTextFileScript3

Each of these will take the conky text file path with -c option and individually start the widgets.


PS: You might face issues if any of the above actions, like the path configuration (in step 6) is not done correctly. Also, This requires little bit of scripting knowledge to work your way around. In a nutshell, these are the minimal steps required to setup Conky-Lua Widgets on Ubuntu.

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Power Saving Tips on Ubuntu 8:07 AM

If you are running 11.10 and suffering from excessive power consumption on your laptop/netbook, I insist upgradation to 12.04 immediately. In the latest 12.04 LTS release, the kernel bug relating to the excess power consumption has been fixed.

On 11.10, my laptop consumed a whooping 31 to 33 W of power. On 12.04, it has fallen down to 24 W. Further more, I've installed these three utilities which seem to have reduced the power consumption from 24 W to 16 W, which is pretty cool.


1) From Ubuntu software center, search for laptop-mode-tools and install it.


2) Install powertop which helps you assess the power consumption details and configure some of the processes. (sudo powertop on terminal to run it after installation)


3) Install jupiter, a tiny applet that runs on startup, a very useful utility that lets you set the mode to power consumption and also lets you configure the bluetooth and wireless options which typically consume a lot of power.


Installation of jupiter :

sudo add-apt-repository ppa:webupd8team/jupiter
sudo apt-get update
sudo apt-get install jupiter
sudo apt-get install jupiter-support-eee

4) If you are on a hybrid-graphics laptop, you can turn off your graphic card. In my case, this worked like a charm. 

echo OFF | sudo tee /sys/kernel/debug/vgaswitcheroo/switch 


However, the above command is not persistent and needs to run on every startup. 


Standard tips like keeping the brightness low, turning off wireless/bluetooth when not needed would also help.
I have abandoned using Ubuntu 11.10 from the past 3 to 4 months because of its excessive power consumption on my Dell Inspiron. Thanks to Precise Pangolin and these three utilities, I am back on Ubuntu now. :)


Hope this helps some of you battling with power consumption issues on laptops and netbooks running Ubuntu.

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