Airport1.java

//AirportCodes1.java , Task ->2 , Date -> 09-04-2015
import java.io.*;
import java.util.Scanner;
import java.util.StringTokenizer;

public class AirportCodes1
{
    public static void main (String[] args) throws IOException
    {

        Scanner user_input = new Scanner( System.in );
        String file_name , airport_name;

        //Take file name
        System.out.print("Enter input file name >> ");
        file_name = user_input.nextLine();

        //Take airport name
        System.out.print("Enter airport name >> ");
        airport_name = user_input.nextLine();

        //Input file
        File file = new File(file_name);
        BufferedReader buffer = new BufferedReader(new FileReader(file));
        String line , token ,previous_token;
        boolean IATA_code_found = false;
        while ((line = buffer.readLine()) != null)
        {

            line = line.trim();
            //Start playing with trimmed line here

            StringTokenizer tokenizer = new StringTokenizer(line ,",");
            //Tokenize the string and use them as instructed in question
            //Previous token is cleverly storing the IATA code
            int i=0;
            previous_token = "";
            while (tokenizer.hasMoreTokens())
             {
                token = tokenizer.nextToken().trim();
                if(i == 1)
                {
                    if(token.equalsIgnoreCase(airport_name))
                    {
                        //You hit a jackpot ,just break from all loops after printing message
                        System.out.println("Airport: "+ token + " has IATA code:"+ previous_token );
                        IATA_code_found = true;
                        break;
                    }
                }

                i++;
                previous_token = token;
             }
             if(i == 1)
             break;
        }

        //If no line is matching the given airport then display not found
        if(!IATA_code_found)
        {
            System.out.println("Airport name: " + airport_name + " was not found");
        }
    }

}