Take a file as input, get the value from file and insert it in a ArrayList after inserting write all the values of list in other file...

sample: 
Input file: input.txt

class Employee

{

     private String name;

     public Integer age;

     protected Date dob;

     public Address addr;

     private Date doj;

     public  String designation;

}

output file: output.txt(Empty file)

InputFile.java

package com.test;

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.FileReader;

import java.io.FileWriter;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.ObjectOutputStream;

import java.util.ArrayList;

public class InputFil

{

       public static void main(String[] args) throws IOException

       {        

           BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

           System.out.println("Enter File Name:");

           String fname=br.readLine();

        try

        {    

            @SuppressWarnings("unused")

            FileInputStream f=new FileInputStream(fname);

            System.out.println("*****************************************************");

             System.out.println("content of file are:");

             System.out.println("************************");

            FileReader file=new FileReader(fname);

            BufferedReader b=new BufferedReader(file);

            String s1=b.readLine();

            while(s1!=null)

            {

                    System.out.println(s1);

                    s1=b.readLine();        

            }

        }

        catch(FileNotFoundException e)

        {

            System.out.println("File not Found");

            return;

        }   

        System.out.println("*****************************************************");

        ArrayList<String>rows = new ArrayList<String>();

        try {

            System.out.println("*****************************************************");

            System.out.println("In Array List :");

            System.out.println("*******************");

            BufferedReader r = new BufferedReader(new FileReader(

                    fname));

            String line = null;

          

            while ((line = r.readLine()) != null)

            {

                String[] arr=line.split("\\s+");

              

                rows.add(line);

            }

            System.out.println(rows.toString());

        } catch (IOException e)

          {

            e.printStackTrace();

        }

            BufferedWriter writer=null;

            writer = new BufferedWriter(new FileWriter("output.txt"));

            //ObjectOutputStream out = new ObjectOutputStream((output));

            String listWord;

              

            for (int i = 0; i< rows.size(); i++)

            {

            listWord = rows.get(i);

            writer.write(listWord);

            writer.write("\n");

            }

            writer.close();   

        }

    }

output of program

Enter File Name:
input.txt
*****************************************************
content of file are:
************************
class Employee
{
     private String name;
     public Integer age;
     protected Date dob;
     public Address addr;
     private Date doj;
     public  String designation;

}
*****************************************************
*****************************************************
In Array List :
*******************
[class Employee, {,      private String name;,      public Integer age;,      protected Date dob;,      public Address addr;,      private Date doj;,      public  String designation;, , }]



open output.txt (we can see all data in input.txt now available in output.txt)

class Employee
{
     private String name;
     public Integer age;
     protected Date dob;
     public Address addr;
     private Date doj;
     public  String designation;

}

Java Program To Print Consecutive characters and the number of times it occurs in ascending order of number of occurrences

Sample 
-----------
 input : “I saw a cd player and a modem in ccd”

     output :  de-->  1 
                  cd --> 2 
                  I saw a player and a mom in c

ContiAlpha.java

package com.test;

import java.io.IOException;

import java.util.ArrayList;

import java.util.Collections;

import java.util.HashMap;

import java.util.Set;

public class ContiAlpha

{

    public static void main(String[] args) throws IOException

    {

      try

      {

        HashMap<String, Integer> map= new HashMap<String, Integer>();

        String s1="I saw a cd  ghplayer and a modem degh in ccd";

        s1=s1.toLowerCase();

        for(int i=0;i<(s1.length()-1);i++)

        {

            if(s1.charAt(i+1)-s1.charAt(i)==1)

            {

                String word=s1.charAt(i)+""+s1.charAt(i+1);

       

                if(map.containsKey(word))

                {

                    int value=map.get(word);

                    map.put(word,++value);

                } 

                    else

                    {

                        map.put(word, 1);

                    }

            }               

        }  

        ArrayList<ContiSortByValue> list=new ArrayList<ContiSortByValue>();

             Set<String> keySet=map.keySet();

             String s2=s1;

             for(String k : keySet)

             {

                  s2=s2.replace(k, "");

                 int value=map.get(k);

                 list.add(new ContiSortByValue(k, value));             

             }

             System.out.println(s2);

             Collections.sort(list);

             for(ContiSortByValue sort : list)

             {

                 System.out.println(sort);

             }

      }   

      catch (Exception e)

      {

            e.printStackTrace();

      }           

    }

}

ContiSortByValue.java 

package com.test;

public class ContiSortByValue implements Comparable<ContiSortByValue>

{

    private String key;

    private Integer value;

    public ContiSortByValue()

    {

        // TODO Auto-generated constructor stub

    }

       public ContiSortByValue(String key, Integer value)

      {

        super();

        this.key = key;

        this.value = value;

      }

    @Override

    public int compareTo(ContiSortByValue obj)

   {    

        return this.value - obj.value;

    }

    @Override

    public String toString()

    {

        return key + "-->" + value;

    }

}

output:

de-->1
cd-->2
i saw a  player and a mom in c 

Java Program toFind duplicates and unique set

Example Input :

  an array of String contains :String[] str = new String[] {"alok", "dhoni", "manish", "rajiv", "alok", "rajiv"}

output : 

 unique items: [manish, dhoni]
Duplicate items : [alok, rajiv]

 SetExampl.java 

package com.alok.Uniqueduplicate;

import java.util.HashSet;

import java.util.Set;

public class SetExample

{

    public static void main(String[] args)

    {

    String[] str = new String[] {"alok", "dhoni", "manish", "rajiv", "alok", "rajiv"};

    Set<String> duplicateSet = new HashSet<String>();

    Set<String> uniqueSet = new HashSet<String>();

        for(int  i = 0; i < str.length ; i++ )

        {

            if(!uniqueSet.add(str[i]))

            {

                duplicateSet.add(str[i]);

            }

        }

        uniqueSet.removeAll(duplicateSet);

        System.out.println("unique items: "+uniqueSet);

        System.out.println("Duplicate items : "+ duplicateSet);

    }

}

output : 

unique items: [manish, dhoni]
Duplicate items : [alok, rajiv]

PROGRAM TO SHOW THE USE OF HasSet, Iterator AND for Loop

HashSet_Example.java

package com.alok;

import java.io.IOException;

import java.util.*;

public class HashSet_Example

{

public static void main(String[] args)throws IOException

{

String str[]={"alok","manish","Pravin","rajiv","pratyush"};

//create a HashSet to store above string

HashSet<String> hs= new HashSet<String>();

//Storing elements to HashSet

for(int i=0;i<str.length;i++)

{

hs.add(str[i]);

}

System.out.println(hs);

//add an iterator to HashSet

Iterator<String> it= hs.iterator();

//Displaying elements using iterator

System.out.println("Retrieve Elements from HashSet using Iterator..");

while(it.hasNext())

{

String s=it.next();

System.out.println(s);

}

//Displaying Elements using For-each loop...

System.out.println("\nRetrieve Elements using for loop....");

for(String var:hs)

{

System.out.println(var);

}

}

}

OUTPUT

[manish, alok, Pravin, pratyush, rajiv]
Retrieve Elements from HashSet using Iterator..
manish
alok
Pravin
pratyush
rajiv

Retrieve Elements using for loop....
manish
alok
Pravin
pratyush
rajiv

Write Your First String Program

First create a POJO class

Right Click on

SRC ( inside application 1)à newà class

Write any package name like I’m writing com.alok and give class name like Book then click finish

package com.alok;

public class Book

{

      private String title;

      private String author;

      public Book()

      {

            System.out.println("Book()");

      }

      public String getTitle() {

            System.out.println("getTitle");

            return title;

      }

      public void setTitle(String title) {

            System.out.println("set title");

            this.title = title;

      }

      public String getAuthor() {

            System.out.println("getAuthor");

            return author;

      }

      public void setAuthor(String author) {

            System.out.println("set Author");

            this.author = author;

      }

     

}

Inside config.xml register this POJO class with a unique bean id

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"

      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

      xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

<bean id="b1" class="com.alok.Book">

      <property name="title" value="java made easy"></property>

      <property name="author" value="prince"></property>

</bean>

</beans>

 à b1 is pointing to a object which is already created then we are calling setTitle and setAuthor 

à inside config.xml, for every bean tag, object is created

à All Setter method is calling before delimiter itself

Now Develop a Client Program

src-->com.alok-->new--> class

BookClient.java

package com.alok;

import org.springframework.beans.factory.BeanFactory;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class BookClient {

public static void main(String[] args) {

BeanFactory fac=new ClassPathXmlApplicationContext(new String[]{"config.xml"});

System.out.println("----111-----");

Book b1=(Book)fac.getBean("b1");

System.out.println("----222-----");

System.out.println(b1.getTitle());

System.out.println(b1.getAuthor());

}

}

à  While creating beanFactory object inside config.xml, corresponding setter and getter method is calling

try to understand output

output:-

Book()

set title

set Author

Book()

set title

set Author

----111-----

----222-----

getTitle

java made easy

getAuthor

prince

First Step in STC

When STC is opened then click on

 FileànewàSpring Project

Give any name, for example I’m giving application 1

Now Right click on

 application 1à propertiesà Java Build Path

Click on adds external JARs and first adds all jar files inside spring-framework-4.0.0.M1/libs

Again click on adds external JARs and add all jar files inside commons-logging-1.1.3

Right Click on  src (inside application 1)ànewàSpring bean configuration file

Give any name like I’m giving config.xml

Contents already exist inside config.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"

      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

      xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

</beans>

Now write your first spring program

Getting Started with Spring

(1) First Download Spring FrameWork
-----> latest version is 4.0

click below link to download spring Framework 4.0
http://www.springsource.org/download/community

download only

spring-framework-4.0.0.M1-dist.zip

(sha1)

47.6 MB

Three inside this Zip folder.

      ---1. docs

      ---2. libs --------> there are several jar files.

      ---3. schema

----------> The whole spring framework is developed in JAVA

(2). Second Download Commons-logging- 1.1.3

   ----> these jar files are using for internally logging purpose

click below link to download Commons-logging- 1.1.3

http://commons.apache.org/proper/commons-logging/download_logging.cgi

from here download commons-logging-1.1.3-bin.zip

(3).  Last Download Spring Tool Suite

        

click below link to download Spring Tool Suite

http://www.springsource.org/downloads/sts-ggts

from here download depend on your computer configuration(32bit or 64 bit)

For Window(32 bit)-  spring-tool-suite-3.2.0.RELEASE-e3.8.2-win32.zip

For Window(64 bit)- spring-tool-suite-3.2.0.RELEASE-e3.8.2-win32-x86_64.zip

After download Spring Tool Suite-3.2.0

--->click on STC icon. now you are ready to write your first spring program

     (Very similar to Eclipse)

(All download links are from http://www.springsource.org   and all right reserved@Spring by Pivotal )