Counting number of lines in text file using javan

We can read lines in a file using BufferedReader class of Java. See the example below −

Example

Consider the following text file in the classpath.

test.txt

This is Line 1
This is Line 2
This is Line 3
This is Line 4
This is Line 5
This is Line 6
This is Line 7
This is Line 8
This is Line 9
This is Line 10

Tester.java

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;

public class Tester {

   private static final String FILE_PATH = "data.txt";
   public static void main(String args[]) throws IOException {
      FileUtil fileUtil = new FileUtil(FILE_PATH);
      System.out.println("No. of lines in file: " + fileUtil.getLineCount());
   }
}

class FileUtil {
   static BufferedReader reader = null;    
   public FileUtil(String filePath) throws FileNotFoundException {
      File file = new File(filePath);
      FileInputStream fileStream = new FileInputStream(file);
      InputStreamReader input = new InputStreamReader(fileStream);
      reader = new BufferedReader(input);
   }

   public static int getLineCount() throws IOException {
      int lineCount = 0;
      String data;        
      while((data = reader.readLine()) != null) {
         lineCount++;                  
      }            
      return lineCount;
   }
}

This will produce the following result −

Output

No. of lines in file: 10