How

How..

When I was studying maths, I learnt that any theorems and assumptions can be proved by 4 methods 
        1)   Direct proof

        2)    Proof by hypothesis

        3)   Proof by mathematical Induction

        4)     Proof by contradiction.

There are some assumptions in life cannot be proved by any of these methods. Ex: existence of God. It cannot be proved but only can felt.  We also heard that we may not use "maths" in every problem of our life but it says every problem has solution/s. Some of them solves by itself, if given enough time.

When I was studying Software Engineering, I found out that there are 4 types of software engineering.

1)      Business critical,

2)      Mission critical

3)      Security critical

4)      Game development

As I have had problem in finding jobs, I come to the conclusion that these developing  jobs are not given to ethnic origins or someone born outside of the country. (Some assumptions of life cannot be proved it can only felt in a bad way *) so three of the above  is hard to get.  I do not want to develop games even though it has lots of money.  I do not want our next generations to be obese and keep them inside and play game all the time. Perhaps there is more fun in playing than developing games.

But every problem has a solution. Rt? I thought there should be one more type of software Engineering.  Software for fun.  This software is based on art. You can get inspiration from anywhere. Trees … flowers … wild flowers.. Animals … bees and birds.Just let your imagination to build your software.  This is limitless …, fun, you can use your mathematics that you are winging about of never used in real life. 

Advantages:

     1)      Fun in developing

     2)      Time Pass keeps you busy.

     3)     To make programming interesting for future generations

     4)      Based on Art as Can use your own imaginations

     5)      Endless. We never run out of ideas.

     6)    Can get inspirations from anywhere

     7)    Designing Industry/Advertising Industries ….

     8)    Unused mathematics learn in school can be used.(but still you won’t get to use complex analysis, integration, differentiation…)

     9)     Going green without paper consumption.

     10)   Software that has wider audience.

Why I used Java: 1) Simple. 2) Easy to Master .3) Lots of Graphic libraries .4) Object Oriented.5) this is not performance oriented. As java is 4^th generation, written on top of c. 

Here by I proved that there is one more type of software development. I call it fun critical. I am sure you like it too.
(* :- All immigrants (ie black people) can also have controlling jobs too.One quality control and another is disease control. ie, testing and toilet cleaning. First you are given black box testing and may be given white box testing after you become completely white  inside your head. Toilet cleaning has nothing to do with your head , just you have to clean the toilet until it becomes crystal white.)

How I combat depressions from gloomy weather of United Kingdom.

 

How To...

Have you ever wondered what is behind the minds of successful people?

Not all people can become successful. Have you ever wondered why? Because successful people are often selfless.  Generally people always wanted to get richer. The person who wants to get rich only for him may become a robber, Person thinking of his wife and children only may end up in a monthly income job. But the one who can thinks of wider audience or one who thinks, “How can I make other people’s life better?” will become successful. The Whole world is part of their life too.

For example Bill Gates, why he has to become successful? He might have thought how can I make everybody can use computer. Life would be much easier if everyone knows how to operate the computer. (Do you remember even computing people struggled in command prompt). Another example I can give is, William Shakespeare who use to write plays and dramas thinking how I can entertain people. (Rather than how can I entertain my family or friends or myself). He had his own friends who can act in dramas that helped him to attract more audience. He might have thought “I think I should write these words for my friend... (Who ever he is) that would be really funny. People would laugh their guts out if it comes from him.... (Who ever he is).  I can give lot more examples in history like Marie Curie, Albert Einstein, Thomas Alva Edison all thought how do I make world a better place? People who have ability to share always get more.

We hear about Jihadist, Sometimes I wondered what they want to prove here.  Do they want to free people? (By sending all of them to heaven) or my life is a mess I would like to see everybody Else's life in a mess too. Some wanted to spread Ebola by contaminating themselves with the virus? Seriously? Not everybody can do that, you have to be strong for proving something. I caught 2 days of flue, and then I thought nobody should get this, even my enemies. I couldn’t sleep for two days with cough and fever and blocked nose. No, I would not wish this would happen to even recruiting people. (:)).

So if you want to become successful, be selfless and be strong and be willing to take risk for good cause. A fool, (who harm themselves and others) or a selfish cannot become successful. 

(forgive me for any grammatical errors or spelling mistakes , I am still learning English)

How To become Successful.

How To...

Proxy Pattern:
Provides a surrogate or placeholder for another object to control access to it. "Proxy" is actually a repesentative of another object.
A "remote Proxy" controls access to a remote object.
A "virtual Proxy" controls access to a resource that expensive to create.
A "protection Proxy" controls access to a resourse based on access rights.(security)
In this blog I am going to explain first one . This involves RMI ie Remote Method Invocation. This is the one topic in Java , I couldn't get to see, or touch.  Again all information here are referenced from Head First Design Patterns Book.

Image is taken from http://www.oodesign.com/proxy-pattern.html

Suppose client wants to call some methods on a object which is in Server's heap. Server is remote to the client and it has to talk to the server which is on the other side of  the network. RMI stub  act as a client proxy on the client's heap , where as RMI Skeleton act as server proxy on the Server's heap. Mainly these proxies help in serialization (write object in server side, readobject in client side-deserializing, This is before java 2. Now a days we can get proxies dynamically on the go. - just note that Proxies are  different pattern from decorator patterns.)
This needs two sides programming
 1) Client  side program or code  which lookup the RMI registry to get the stub object ,client invokes the method on the stub object, as if the stub is the real service.
       MyInterface service = (MyInterface)Naming.lookup("rmi://127.0.0.1/RemoteHelloworld");
2)Server side programming to give service.
           5 steps for these.
    i) Make a  Remote interface
            a)Extend java.rmi.Remote
              b)Declare that all methods throw a RemoteException.
               c)be sure arguments and return values are primitives or Serializable.
              import java.rmi.*;
                public interface MyRemoteInterface extends Remote {
                  public String helloWorld () throws RemoteException;
                 }
           ii)Make a Remote implementation
                a)Implement the Remote interface
                  b)Extend UnicastRemoteObject
                   c)Write a no-org constructor that declares a RemoteException
                   d)Register Service with the RMI registry
              public class MyImplementation extends UnicastRemoteObject implements MyRemoteInterface {
   public MyImplementation() throws RemoteException {}
      public String helloWorld() {
           return "hello world";
}
//more code
}
In tester in the main method you register the service with the RMI registry
  try {
MyInterface service = new MyImplementation();
Naming.rebind("RemoteHelloworld",service); //  you can give any name to hide your object.
} catch (Exception ex){....}
iii) generate stubs and skeletons
        run rmic on the remote implementation class (not on remote interface)
           %rmic MyImplementation
  iv)run rmiregistry
        bring up a terminal and start the rmiregistry
     %rmiregistry
v)start the service
        bring up another terminal and start your service
%java MyImplementation
 (run the main method of service impementation class)
Suppose I am a client wants to monitor some dogs at remote service. Then,
 First on the server side, we have to make the service available.
To make remote interface:
     import java rmi.*;
    public interface DogRemote extends Remote {
        public int getMicroChipNo() throws RemoteException;
        public String getSpecies() throws RemoteException;
         public String getLocation() throws RemoteExcetion;
         public String getCondition() throws RemoteExeption;
}
If you want to make a method like
public Collar getCollar() throws RemoteException; then you have to make "Collar " Serializable.  Just you can do public class Collar implements Serializable  or extends serializable .(there is no methods to implement).But you have to import java.io.*;   If the class contains any other objects you can make them serializable or declare it as transient.
make remote implementation
import java.rmi.*;
import java.rmi.server.*;
public class Dog extends UnicastRemoteObject implements DogRemote
//instance variable here
public Dog(String location,String species,int microchipno) throws RemoteException{
//code here
}
public int getMicroChipNo() {
    return microchipno;
}
public String getSpecies(){
return species;
}
// all other get codes here
}
Registering with RMI registry
public class DogTester {
   public static void main(String[] args){//you can also input arguments here.
try {
DogRemote pudsy = new Dog("London","poodle", 1234);
Naming.rebind("//"+"London.dogcanal.com" + "/dog",pudsy);/**here you can add differnt locations and different names for objects by passing args if you want.**/
}catch (Exception e){
e.printStackTrace();
}
}
}
Then run rmiregistry followed by the main method of DogTester.
On the client side,
Class to monitor dog and a tester
import java.rmi.*
public class DogMonitor{
  DogRemote pudsy;
public DogMonitor (DogRemote pudsy){
this.pudsy = pudsy;
}
public void dogDetails(){
try
{
      System.out.println("Dog from"+pudsy.getLocation());
     System.out.println("Dog Species"+pudsy.getSpecies());
      System.out.println("Condition"+pudsy.getCondition());
      System.out.println("Microchip number"+getMicroChipNo());
}  catch (RemoteException e){
e.printStackTrace();
     }
   }
}
Write a monitor tester
      import java.rmi.*;
     public class DogMonitorTester{
            public static void main(String[] args){
                  try
                     {
                          DogRemote  pudsy = (DogRemote)Naming.lookup("rmi://London.dogcanal.com/dog");
                          DogMonitor monitor = new DogMonitor(pudsy);
                            }
                              catch (Exception e){
                                    e.printStackTrace();
                             }
                         }
                          monitor.dogDetails();
}
}

       How to monitor dogs( or objects) remotely.             

Comments are welcome. (So that I can correct my mistakes)

How To...

Singleton Pattern:
"Ensures a class has only one instance, and provides a global point of access to it."
Here we are making a class , which has only one instance which is instanciated within itself and we never let any other class to make another instance.
we are providing a global access point to the instance. - Head first design pattern.
ex: servelets.

This picture is taken from  http://www.oodesign.com/singleton-pattern.html.

When restricting access , we always have to think about make something a "private". The method which instanciates object is the constructor. So we make constructor "private". When constuctor made private, it should be instanciated in a static method/variable so as to give global access. When you think of global access , make it thread safe.
public class Singleton{
private static Singleton uniqueInstance;
private Singleton(){}
public static synchronized Singleton getInstance() {
if (uniqueInstance == null) {
uniqueInstance = new Singleton();
}
return uniqueInstance;
}
}
To improve Multitreading
1) Do nothing if the performance of getInstance() is not critical
2)If your application always creates and uses singleton then create Singleton eagerly as JVM creates it when the class is loaded.
       public class Singleton {
          private static Singleton uniqueInstance = new Singleton();
      private Singleton(){}
    public static Singleton getInstance() {
        return uniqueInstance;
    JVM ensures that instance will be created before any thread can access to the static instance variable.
3)Use double-checked locking to reduce the use of sychronization in getInstance() - synchronization kills performance
public class Singleton{
   private volatile static Singleton uniqueInstance;
private Singleton(){}
public static Singleton getInstance(){
if (uniqueInstance == null){  /** only enter the block if it is null. this means it enters synchronized block only once for the first time.**/
synchronized (Singleton.class){
if (uniqueInstance == null)   /** double checking just in case first one checked by  two threads simultaniously  as one of them will succeeds,  other one waits just outside after first checking.**/
   uniqueInstance = new Singleton();
}
}
return uniqueInstance;
}
}
These are all referenced from "Head First Design Patterns" Since I do not want to mess  up with singleton pattern.
Time for our own Singletons. Let us think of Central heating System , and house as a class loader.(one singleton per one class loader). It has only one instance and anybody in the house can have access to it (global) .
I create them eagerly since I bought my house in the winter.(just kidding)

public class HeatingSystem {
private static HeatingSystem uniqueInstance = new HeatingSystem();
private static Temperature ;
//currentTime == calender.getTime();
private HeatingSystem(){}
public static HeatingSystem getInstance(){
return uniqueInstance;
}
public void setTimer(Time startTime, Time endTime){
        if (currentTime.equalsTo( startTime))
            onSystem();
       else if (currentTime .equalsTo(endTime))
            offSystem();
/** to get current time you can use
Calendar calender = Calendar.getInstance();
CurrentTime = calender.getTime();**/

}
public  void setTemp(Temperature temp)
{
        this.Temperature = temp;
}
public void onSytem(){
    // press the button
}
public void offSystem(){
//undo the pressed button
}
}
Now everybody has only one instance , and has global access to that instance. Husband gets the instance switch on the system, He forgets all about it and when he sees the gas bill he could  blame it on the wife since she had the same instance  and access, so he expected her to switched it off as it is her responsibility too.

How to fight over your Gas Bill. (All  characters here are fictitious , if it resembles someone or some incidents then it is purely coincidental).

How To....

The Command Pattern:
"Encapsulates a request as an object, thereby letting you parameterise other objects with different requests queue or log requests and support undoable operations."
It supports the decoupling of the invoker of a request and receiver of the request.
-Head First Design Patterns.
ex: Home automation systems,  ... or where ever you have to press the bottons then think of you as a client and the webpage which holds the button as innocent invoker(he is not responsible for all unexpected actions :))

 This Picture is from:
http://www.oodesign.com/command-pattern.html
 I remembered my dissertation in MSc. Jobs come to the server in a queue, and these jobs are discarded once they are done with it. 
Let us think about Briton got talent.  Let us say "ITV"  is our client. Ant&Deck are (is) our invoker/s. All vendors have different kinds of act to show. Our commands are performing acts.  This is the audition taking place some where in Birmingham  and it is a all day process and people can come anytime between 9am - 5pm and put thier name in the list carried by our invoker (Ant&Deck).  They have nothing to do with who is doing the act. They just have to announce thier name  according to the list and all acts are come as a surprise. Simon Cowell , Alesha Dixon ... undo button invokers.
public interface PerformingAct{
public void perform();
}
public class SingingAct implements PerformingAct{
Team team;
public SingingAct(Team team){
this.team =team;
}
public void perform(){
team.sing();
}
public class StopSingingAct impements PerformingAct{
Team team;
public StopSingingAct(Team team){
this.team =team;
}
public void perform(){
team.retreat();
}
}
Same way we can implement DancingAct, MimingAct,ScreamingAct....and stoping all those acts in a class.
This is our invoker.
public class Invoker{
ArrayList acts;//you can also use a LinkedList or a Queue.
   static PerformingAct stopact;
static int count ==0 ;
public Invoker(){
acts =  new ArrayList();// all invoker may have a list for marking purposes.
}

public void addAct(PerformingAct act){
acts.add(act);
}
public void announce(PerformingAct act){

setStopAct(act);
//check the size of the arraylist here
  PerformingAct act1 = (PerformingAct)acts.remove(0);
act1.perform();
}
public void xbottunPushed(){
count = count+1;
if( count >=2){
stopact.perform();
count ==0;
}
}
public void setStopAct(PerformingAct act){
stopact = act;
}
}
On the day of audition,
public class LoadPerformingActs{
public static void main(String[] args){
Invoker antdeck = new Invoker();
Invoker simon = new Invoker();
Invoker alesha = new Invoker();

Team teamA = new Team();
Team teamB = new Team();
PerformingAct diversity = new DancingAct(teamA);
PerformingAct stopDiversity = new StopDancingAct(teamA);
PerformingAct mindBlowing = new SingingAct(teamB);
PerformingAct stopMindBlowing = new StopSingingAct(teamB);
antdeck.add(diversity);
antdeck.add(mindBlowing);
antdeck.announce(stopDiversity);
simon.xbottonPushed();//this needs thread synchronization
alesha.xbottonPushed();/**this needs thread synchronization in real life. Here we assume that alesha and simon does not push the button at the same time.
.......
continues until 5 pm. **/
}
}
Just have to remember if  you make a class for commands they can be set in a queue and invokers only remember to execute the commands and  all actions are vendors' responsibility. 
  In this way commands helps  Invokers to detach themselves from responsibilities.

How to detach yourself from responsibilities. :>)

How To....

The Template Method Pattern :
"Defines the skeleton of an algorithm in a method,defering some steps to subclasses.Template Method lets subclasses redefine certain steps of an algorithm without changing the algorithm's structure"
Principle used : The Hollywood Principle i.e "Don't call us,we'll call you" (ha ha "never")
Here High level components determine "when"  lower level components are needed and how they are used, but  letting low level components to hook themselves into the system.
- head first design patterns book.

http://www.oodesign.com/template-pattern.html
Couple of months back I was annoyed by the dailymail article about how men look at  women.
For your information this is the article.
What are you staring at? Scientists reveal how our brain sees men as people, but women as body parts (and it's not just men who do it)

Read more: http://www.dailymail.co.uk/sciencetech/article-2179164/Double-vision-How-brains-men-people-women-body-parts.html#ixzz2rgMM8Kr7.
Let us think of a project for the men to create perfect woman.Let  "PerfectWoman" is an abstract class.
GarysPerfectWoman, PetersPerfectWoman are two concreate implementations.
public abstract class PerfectWoman{
// here you have some stuff to do. you need a media tackers,a graphic,a canvas ...., I only give general ideas it is not the full implementation

final void drawPerfectWomanImage(){

    drawHeadImage();
      drawUpperBodyImage();
     drawLowerBodyImage();
      drawLegImage();
      drawString();//this is the hook which does nothing.
}
      abstract void drawUpperBodyImage();
      abstract void drawLowerBodyImage();
  final void drawHeadImage(){
      g. setImage("kimkardashianheadImage.jpg" ,20.00,20.00,c);/** you never know whose head in that jpg**/
}
   final void drawLegImage(){
    g. setImage("JenniferLopezLeg.jpg",20.0,400.00,c);/** but you never know whose legs are  in that jpg**/
}
    void drawString(){}/** does nothing here , you can name your own name or you can leave this as it is.**/
}
Concreate implementation:
public class GarysPerfectWoman extends PerfectWoman{
// constructors not shown
public void drawUpperBodyImage(){
g.setImage("kieraknightlyUpperbodyimage.jpg",20.0,100.0,c);/** like this you can set your own picture.**/
}
public void drawLowerBodyImage(){
   g.setImage("jenniferLopezLowerBodyImage.jpg",20.0,200.0,c);
}
}
now some where in the tester
  PerfectWoman garys = new GarysPerfectWoman();
     garys. drawPerfectWomanImage();/** that draws a perfect woman for Gary , but Gary cannot change the head or leg.(we never let Gary to hurt  the feelings of good women)**/
In this way high level components controls the flow of the program and holds some control over some parts of the program.

title:

How to  draw image of a perfect woman without photoshop but with some guidelines.

How To....

The Observer Pattern:
"defines a one-to- many dependency between objects so that when one object change state ,all of its dependents are notified and updated automatically"
Design Priciple used:Strive for loosely coupled designs between objects that interact.
- Head first Design Patterns

The above picture is taken from http://www.oodesign.com/observer-pattern.html

Now is the time to understand life of a celebrity,let us say Wendy. Way back then ,when she wasn't a celebrity, she had only 3 friends. Susy, Loosy(she won't mind if I spelt her name wrong), Jenny. If she had something to say to them she knows how to say to them. Since for Susy, she just have to email her since she works in a office and mobile phone  is not allowed in there. (Her boss is too bossy). For Loosy , she had to text her since she is always outgoing and very busy. For Jenny she has to ring home since she is a house wife. (never checks email or mobile phones).
so if she has to give any updates she has to do
susy.email();
loosy.text();
jenny.ring();
Now she is a celebrity ie she is a subject so that everybody wants to hear her updates. She do not know everyone and she is busy to give everyone her updates. Now what should she do? I think she has to do a "Twitter" account. Everyone who wants to follow her (that is our observers) have to have some common methods so that she doesn't have to know everybody and thier needs. Let us consider one to many relationships and how to make class loosely coupled.Note that this is not our actual real life twitter.(a sort of)
Let us consider "Twitter" is our subject interface(it could be abstract also). Let us say "Follower" is our observer. There might be another interface "Communicator" depending on the needs.
public interface Twitter{
public void follow(Follower fl);
public void removeFollwer(Follower fl);
public void acknowledgeFollowers();
}
public interface Follower{
public void updateStatus(String tweet);
}
public interface Communicator{
public void communicate();
}

public class CelebrityTwitter implements Twitter {
     private ArrayList followers;
      private string tweet;
public CelebrityTwitter() {
    followers = new ArrayList();
}
public void follow(Follower fl){
       followers.add(fl);
}
public void removeFollower(Follower fl){
int k = followers.index(fl);
if (k>=0)
followers.remove(k);
}
public void acknowledgeFollowers(){
for (int i=0;i<observers.size();i++){
Follower follower = (Follower)followers.get(i);
follower.updateStatus(tweet);
}
public void setTweet(String tweet){
this.tweet =tweet;
acknowledgeFollowers();
}
}
Concreate implementation of Follower and Communicator
public class EmailCommunicator implements Follower,Communicator{
private string  tweet;
private Email email;
private Twitter  celebrityTwitter;
public EmailCommunicator(Twitter celebrityTwitter,Email email){
this.celebrityTwitter = celebrityTwitter;
this.email =email;
celebrityTwitter.follow(this);
}
public void updateStatus(String tweet){
this.tweet = tweet;
communicate();
}
public void communicate(){
email.send(tweet);
//phonenumber.sendText(); in case of TextCommunicator()
/**by the way this is not the way you actually send email. for that you have to import all these(

import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;
import javax.activation.*;

and do some more stuff ) **/
}
}
Same way you can have lots of comunicator and Follower combinations.TextCommunicator,VoiceMailCommunicator..... all implement  "Follower" and "Communicator"  with different way of communications in communicate() method.
public class TwitterProfile{
public static void main(String[] args){
Twitter wendyTwitter = new CelebrityTwitter();
Email susyEmail = new Email("susy@email.com");
EmailCommunicator susycommunicator = new EmailCommunicator(wendyTwitter,susyEmail);
..........
TextCommunicator loosyCommunicator = new TextCommunicator(wendyTwitter, loosyphone);
.........
wendyTwitter.setTweet(" I am working on a film");
wendyTwitter.setTweet("I am going home from film  shooting");
........
Now everyone is Happy.   Wendy doesn't have to know everyone, as long as you follow her you get her tweeting updates as you desired.

Hence the title:

How To follow a celebrity without stalking.