Question

public class Main {


public static void main(String[] args)
{
int ch = 0;
do
{

Scanner in = new Scanner(System.in);

String s;
System.out.println("Enter the part number");
s=in.nextLine();

try{

  BufferedReader br = new BufferedReader(new FileReader("C:\\Users\\Ankit\\Documents\\NetBeansProjects\\tcs_1\\number.txt"));
  BufferedReader Br = new BufferedReader(new FileReader("C:\\Users\\Ankit\\Documents\\NetBeansProjects\\tcs_1\\number1.txt"));

  String strLine;
  int flag=0;
  while ((strLine = br.readLine()) != null)
  {
        if(strLine.equals(s))
        {
            flag=1;
            System.out.println ("Part Number exists in 1");
            break;
        }
        else
        {
            flag=0;
            System.out.println ("Part Number doesnot exist in 1");
            break;
        }


    }

    if(flag==0)
    {

        while ((strLine = Br.readLine()) != null)
        {
            if(strLine.equals(s))
            {
                System.out.println ("Part Number exists in 2");
                break;
            }
     else
            {
                System.out.println("File does not exist in 2");
                break;
     }

        }
    }
        System.out.println ("Do you want to continue-Press1 for yes and 2 for no");

        ch= in.nextInt();
        br.close();
        Br.close();

}
catch (Exception e)
{
    System.err.println("Error: " + e.getMessage());
  }
}
while(ch==1);
  }
}

this is the program that I made to search a user given string from 2 diff text files. Its working fine but only searching the first line.
eg.: If a file has
1000
1001
1002
it wll only search 1000. How do I go to next line and keep on using the .equals() method?

Answer 1

You should use Scanner not BufferedReader as it’s a more recent class
and I feel does a nicer job with this task. Especially since you have
already used Scanner elsewhere in your code and thus imported it.
Below is a scanner that will read all the lines in a file while there
is a next one to read.

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class JavaApplication32 
{
    public static void main(String[] args) 
    {
        Scanner keyboard = new Scanner(System.in);
        Scanner scanner1 = null;
        Scanner scanner2 = null;
        String partCheck;
        String repeatLoop;
        boolean isInOne;
        boolean isInTwo;

        File file1 = new File("data1.txt");
        File file2 = new File("data2.txt");

        try
        {
            scanner1 = new Scanner(file1);
            scanner2 = new Scanner(file2);
        }
        catch(FileNotFoundException e)
        {
            e.printStackTrace();
        }
            do
            {
                isInOne = false;
                isInTwo = false;
                System.out.println("Enter the part number");
                partCheck = keyboard.nextLine();
                while (scanner1.hasNextLine() && !isInOne)
                {
                    String line = scanner1.nextLine();
                    if(line.equals(partCheck))
                    {
                        System.out.println("Part Number exists in 1");
                        isInOne = true;
                    }
                }
                if(!isInOne)
                {
                    System.out.println("Part Number does not exist in 1");
                }
                while(scanner2.hasNextLine() && !isInOne && !isInTwo)
                {
                    String line = scanner2.nextLine();
                    if(line.equals(partCheck))
                    {
                        System.out.println("Part Number exists in 2");
                        isInTwo = true;
                    }
                }
                if(!isInTwo)
                {
                    System.out.println("Part Number does not exist in 2");
                }
                System.out.println("Do you want to continue? (Y/N)");
                repeatLoop = keyboard.nextLine();
            } while(repeatLoop.equalsIgnoreCase("y"));
        scanner1.close();
        scanner2.close();
    }
}

Example Text File data1.txt:

Test1
Test2
Test3
Test4

Example Test File data2.txt

Check1
Check2
Check3
Check4

Example stdout when code is run with these datafiles:

run:
Enter the part number
Test1
Part Number exists in 1
Part Number does not exist in 2
Do you want to continue? (Y/N)
y
Enter the part number
Check1
Part Number does not exist in 1
Part Number exists in 2
Do you want to continue? (Y/N)
n
BUILD SUCCESSFUL (total time: 19 seconds)

You also shouldn’t put all of your read in information in a loop. By
putting do at the top you effectively keep creating a new set of
BufferedReaders and naming them the same thing and telling to do the
same thing and then telling them to break after the first hit. If you
did actually get rid of the break you’d have even more problems since
all of this other stuff is in the loop where it shouldn’t be.