How to delete the specified line in file?

Question

How to delete the specified line in file? In case of deleting a specified line in a file, how to do?
Line 1
Line 2
Line 3
Line 4
Line 5
The case is a file including the above content. Now I wanna to delete the "Line 3" and how to realize the action in Java?

Answer 1

An alternative solution can be :
import java.io.LineNumberReader;
import java.io.IOException;
import java.io.File;
import java.io.FileReader;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.PrintWriter;
public class LineDeleter {
public static void main(String args[]){
try {
//suppose you want to delete line 3
     int lineToBeDeleted = 3;
     File f = new File("line.txt");
     long fileSize = f.length();
//Wrap the FileReader with a LineNumberReader. It will help you
//identify the lines.
LineNumberReader lnr = new LineNumberReader( new FileReader(f));
//Wrap the FileWriter object with BufferedWriter object. Create it with the buffersize
//equal to the file size.
     BufferedWriter bw = new BufferedWriter(new FileWriter(new File("line1.txt")),(int)fileSize);
//Wrap BufferedWriter object with PrintWriter so that it allows you
//to print line by line
PrintWriter pw = new PrintWriter(bw);
     String s=null;
     while ( (s=lnr.readLine())!=null ){
          System.out.println(s);
          int lineNumber = lnr.getLineNumber();
//match the line number
          if(! (lineNumber==lineToBeDeleted)){
               pw.println(s);
          pw.flush();
          lnr.close();
          pw.close();
     catch(Exception e){System.out.println(e);}
If you want you can rename the line1.txt to the original file name.
I hope this helps.Good luck!!!!!!