Java program to remove duplicate word from a file without using Collection framework.

In an interview with Oracle one of my friend found this problem how to remove duplicate occurrence of a given word from a file without using collection framework. Since, Set interface of Collection API is a best and easy choice in the case of no duplication. But what to do in the problems when we are asked not to use Collection.

INPUT: TEST TEST TEST RESULT RESULT TEST

WORD TO REMOVE DUPLICATE: TEST

OUTPUT: TEST RESULT RESULT 

Java program 

//RemoveDuplicate.java

import java.io.*;

class RemoveDuplicate 

{

public final String INPUT_FILE="Test.txt";

public final String OUTPUT_FILE="Output.txt";

public int count=0;

public void checkDuplicate(String wordToCheck) throws Exception

{

BufferedReader br=new BufferedReader(new FileReader(INPUT_FILE));

BufferedWriter bw=new BufferedWriter(new FileWriter(OUTPUT_FILE));

StringBuilder sb=new StringBuilder();

while(br.ready())

{

sb=sb.append(br.readLine());

}

String data=sb.toString();

String values[]=data.split(" ");

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

{

String arrVal=values[i].trim();

if(arrVal.equalsIgnoreCase(wordToCheck))

{

count=count+1;

if(count>1)

{

continue;

}

else

{

bw.write(arrVal+" ");

}

}

else

{

bw.write(arrVal+" ");

}

}

bw.flush();

br.close();

bw.close();

}

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

{

new RemoveDuplicate().checkDuplicate("Result");

}

}

Note: Make sure input file is available at given location. 

Input file 

Text.txt

                                   

Output file

Output.Txt

Above java code file can be downloaded by clicking here.