Find duplicate characters in String ?

package com.JavaInterview.Programs;

/**
 * Find Out Duplicate
 * 
 * @author:http://javainterviewprograms.blogspot.in/
 * 
 */

import java.util.*;

import java.util.HashMap;

import java.util.Set;

public class DuplicateCharacters {

 public void findDuplicate(String str)

 {

  char[] charc=str.toCharArray();

  Map<Character,Integer> mapc=new HashMap<Character,Integer>();

  for(Character ch:charc)

  {

   if(mapc.containsKey(ch))

   {

    mapc.put(ch,mapc.get(ch)+1);

   }

   else

   {

    mapc.put(ch,1);

   }

  }

  Set<Map.Entry<Character, Integer>> entrySet=mapc.entrySet();

  System.out.printf("list of duplicates characters in string '%s' %n",str);

  for(Map.Entry<Character, Integer> entry:entrySet)

  {

   if(entry.getValue()>1)

   {

    System.out.printf("%s:%d%n",entry.getKey(),entry.getValue());

   }

  }

 

 }

 public static void main(String args[])

 {

  Scanner input=new Scanner(System.in);

  System.out.println("Please enter the string to find out duplicate Characters :");

  String str=input.next();

  DuplicateCharacters dc=new DuplicateCharacters();

  dc.findDuplicate(str);

 }

}

Output:

Please enter the string to find out duplicate Characters :

papaya

list of duplicates characters in string 'papaya' 

a:3

p:2

Thread: Producer -Consumer Problem ?

package com.JavaInterview.Programs;

import java.util.concurrent.BlockingQueue;

import java.util.concurrent.LinkedBlockingQueue;

/**
 * Producer Consumer Problem
 * 
 * @author:http://javainterviewprograms.blogspot.in/
 * 
 */

public class ProducerConsumer {

 public static void main(String args[]) {

  BlockingQueue sharedQueue = new LinkedBlockingQueue();

  Thread pd = new Thread(new Producer(sharedQueue));

  Thread cs = new Thread(new Consumer(sharedQueue));

  pd.start();

  cs.start();

 }

}

class Producer implements Runnable {

 private final BlockingQueue sharedQueue;

 Producer(BlockingQueue sharedQueue) {

  this.sharedQueue = sharedQueue;

 }

 @Override

 public void run() {

  for (int i = 0; i < 10; i++) {

   try {

    System.out.println("Produced" + i);

    sharedQueue.put(i);

   } catch (InterruptedException e) {

    e.printStackTrace();

   }

  }

 }

}

class Consumer implements Runnable {

 private final BlockingQueue sharedQueue;

 Consumer(BlockingQueue sharedQueue) {

  this.sharedQueue = sharedQueue;

 }

 @Override

 public void run() {

  for (int i = 0; i < 10; i++) {

   try {

    System.out.println("Consumed" + sharedQueue.take());

    sharedQueue.put(i);

   } catch (InterruptedException e) {

    e.printStackTrace();

   }

  }

 }

}

Output :

Produced0

Produced1

Consumed0

Produced2

Consumed1

Produced3

Consumed0

Consumed2

Produced4

Consumed1

Produced5

Consumed3

Produced6

Consumed2

Produced7

Consumed3

Produced8

Consumed4

Produced9

Consumed4

Write a program for Palindrome Number ?

package com.JavaInterview.Programs;

import java.util.*;

/**
 * Find Out Palindrome Number
 * 
 * @author:http://javainterviewprograms.blogspot.in/
 * 
 */

public class PalindromeNumber {

 public static boolean isPalindrome(int number) {

  int palindrome = number;

  int rev = 0;

  while (palindrome != 0) {

   int remainder = palindrome % 10;

   palindrome = palindrome / 10;

   rev = rev* 10 + remainder ;

  }

  if (rev == number) {

   return true;

  } else 

  {

   return false;

  }

 }

 public static void main(String args[]) {

  Scanner input = new Scanner(System.in);

  System.out.println("Please enter a Number");

  int number = input.nextInt();

  if (isPalindrome(number)) {

   System.out.println("The number " + number + " is a Palindrome");

  } else {

   System.out.println("The number " + number + " is NOT a Palindrome");

  }

 }

}

Output :

Please enter a Number

456654

The number 456654 is a Palindrome

Write Program for Fibonacci Series ?

package com.JavaInterview.Programs;

import java.util.*;

/**
 * Find Out Fibonacci Series
 * 
 * @author:http://javainterviewprograms.blogspot.in/
 * 
 */
public class FibonacciSeries {

 public static void main(String args[]) {

  Scanner input = new Scanner(System.in);

  System.out.println("Please enter length of series : ");

  int length = input.nextInt();

  int feb[] = new int[length];

  feb[0] = 0;

  feb[1] = 1;

  for (int i = 2; i < length; i++) {

   feb[i] = feb[i - 1] + feb[i - 2];

  }

  System.out.println("Fibonacci Series of length " + length + ":");

  for (int i = 0; i < length; i++) {

   System.out.print(feb[i] + " ");

  }

 }

}

Output :

Please enter length of series : 

10

Fibonacci Series of length 10:

0 1 1 2 3 5 8 13 21 34