Small doubt

Question

hi friends, how can i update in a flat file like ( abc.txt). i would like to search a string in file and replace something in the row and update
in the same position. how to do that.
with regards.

Answer 1

Try this, this sample read and write the file 'x.x', put your code in the write_1 method.
import java.io.*;
public class RandomF
     RandomAccessFile rf;
public  RandomF() 
     String s;
     long   p;
     try
          rf = new RandomAccessFile("x.x","rw");
          p  = rf.getFilePointer();
          s  = rf.readLine();
          while (s != null)
               write_1(s,p);
               p = rf.getFilePointer();
               s = rf.readLine();
          rf.close();
     catch(FileNotFoundException e)
     catch(IOException e)                                     
public void write_1(String s, long wp)
     try
          long p = rf.getFilePointer();
          rf.seek(wp);
// put your code here
          rf.writeBytes(s);
          rf.seek(p);
     catch(IOException e)                                     
public static void main (String[] args) 
     new  RandomF();
}