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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