Difference in reading file when using a string variable

Question

I have written below code for reading a file:

package com.test.application;

import java.io.*;
import java.io.IOException;

public class FileRead {

    public static void main(String[] args) {
        try{
            File file=new File("Hello.txt");
            FileReader fileReader=new FileReader(file);

            BufferedReader reader=new BufferedReader(fileReader);

            /*String line=null;
            while((line = reader.readLine())!=null){
                System.out.println(line);
            }   */

            System.out.println("This is using no string variable!!!");
            while(reader.readLine()!=null){
                System.out.println(reader.readLine());
            }   
            reader.close();
        }       
        catch(IOException e){

        }

    }

}

my text file is:

What is Lorem Ipsum?
Lorem Ipsum is simply dummy text of the printing and typesetting  
industry. 
Lorem Ipsum has been the industry's standard dummy text ever since the     
1500s, when an unknown printer took a galley of type and scrambled it    
to make a type specimen book. 
It has survived not only five centuries, but also the leap into 
electronic typesetting, remaining essentially unchanged. 
It was popularised in the 1960s with the release of Letraset sheets 
containing Lorem Ipsum passages, and more recently with desktop 
publishing software like Aldus PageMaker including versions of Lorem 
Ipsum.

My question here is when i am using a String variable to read from file, i ma getting all contents of file, i.e:

String line=null;
while((line = reader.readLine())!=null){
    System.out.println(line);
}   

however when i used the below code snippet for reading through file, few lines where skipped, and whole of the file was not getting read.

while(reader.readLine()!=null){
    System.out.println(reader.readLine());
}   

Can anyone please explain why this is happening.

Answer 1

This could be happen because in your non-string variable case you call readLine() twice, and print just second item. Each readLine() call reads line from file and moves current position pointer to the next line. I suggest you to use an intermediate string variable.

Answer 2

You call .readLine() twice, first in while and second in println and only second one is going to output.

Answer 3

In your second snipped you are calling reader.readLine() twice. Every call "consumes" a line, so you're only printing every second line.