how can we remove blank lines from a .txt

[Camden]

Copy a file to another file removing all blank lines.

Typical Input
Here is an

input text with just two

blank lines.

Typical Output
Here is an
input text with just two
blank lines.

coding till now (im using acm library, dont pay attention on readLine()):

String inputFile = readLine("Insert file: ");
            BufferedReader inputFileReader = new BufferedReader(new FileReader(inputFile));
            String inputFileLine;
            String NewFile = readLine("Insert file name of the new file: ");
    		PrintWriter outputFile=new PrintWriter (new FileWriter(NewFile));
    		while((inputFileLine = inputFileReader.readLine()) != null) {
           	char [] characters= inputFileLine.toCharArray();
           	for (int i=0; i<characters.length; i++){
            	 outputFile.print(characters[i]);
                     }
            outputFile.println("");
            } 
            inputFileReader.close();
            outputFile.close();

[hardwired]

import java.io.*;
import java.util.Scanner;

public class IOTest {
    public static void main(String[] args) throws IOException {
        Scanner scanner = new Scanner(System.in);
        System.out.println("Insert file: ");
        String inputFile = //scanner.nextLine();
                           "ioTestIn.txt";
        BufferedReader inputFileReader = new BufferedReader(
                                         new FileReader(inputFile));
        String inputFileLine;
        System.out.println("Insert file name of the new file: ");
        String NewFile = //scanner.nextLine();
                         "ioTestOut.txt";
        scanner.close();
        PrintWriter outputFile = new PrintWriter(new FileWriter(NewFile));
        while((inputFileLine = inputFileReader.readLine()) != null) {
            if(inputFileLine.length() == 0)
                continue;
            outputFile.println(inputFileLine);
        } 
        inputFileReader.close();
        outputFile.close();
    }
}

ioTestIn.txt

Here is an 

input text with just two 

blank lines.

[reachjava]

How to do this with out writing to a new file, just to read the input from a string variable with empty lines in it and store the result to a new String varaiable, after the empty lines are removed.

[Norm]

read the input from a string variable with empty lines in it and store the result to a new String varaiable, after the empty lines are removed.

One way would be to use the Scanner class to "read" the lines from the String.
Concatenate the non empty lines to the new String variable.

[stchman]

One approach would be to do this:

Assumptions:
file 1 exists
file 2 will be created

Pseudo Code:

Open file 1 for reading
Open file 2 for writing

while true
    if file1 != ready // EOF encountered
        break

    String line = readline
    
    if readline == blank
        // do nothing
    else
        write to file 2

end while

close file1
close file2

[reachjava]

Hi,
Thank you for the post. My requirement is not to write to a new file, I will be getting file content in a String variable, in that empty lines will be there at the end of the file, I want to remove these empty lines and put it into a new String variable and I have to use that new variable for further processing...

Thanks..

[reachjava]

I tried this norm.. Want I want to know is by default outputStreamWriter,FileWriter and PrintWriter writes a empty line at the end of the file? which writes stops the cursor exactly at the last content line in the file?

Thanks..

[Junky]

I want to remove these empty lines and put it into a new String variable and I have to use that new variable for further processing

This is a bad idea if your file is large and you will run out of memory.

[Junky]

I tried this norm.. Want I want to know is by default outputStreamWriter,FileWriter and PrintWriter writes a empty line at the end of the file? which writes stops the cursor exactly at the last content line in the file?

Huh?

In the above post you say you will not be creating a new file. So why are you asking about all these writer classes that are used for writing out to a file?

[reachjava]

No, this won't be a large file, it will have not more than 20 lines. I have to use it in another tool, there I have to retrieve the file as a String, there I have to do the remaining process, like removing the empty lines and to use that new variable.

[reachjava]

hi master, if you are interested in replying, pls reply, other wise leave it.. why you are saying all this.. Is there anything wrong in knowing, what is not clear or not known from the experts!!

[Junky]

Are you talking to me? You are not making any sense. All I am trying to do is get you to clarify what you are trying to do. If you don't want my help then I don't give a damn. No skin of my nose.

[Norm]

want to know is by default outputStreamWriter,FileWriter and PrintWriter writes a empty line at the end of the file?

I don't think they do. Is it happening with a program that you have written?
Can you post a SSCCE to show the problem?