Reading and Writing from a text file at the same time

I know who to use the Scanner and PrintWriter to read from and write to a .txt file. But these are limited. How can I read and write at the same time? Such as open a file and change every third character or change every second word to something else and then write it back. I found this [http://java.sun.com/docs/books/tutorial/essential/io/|http://java.sun.com/docs/books/tutorial/essential/io/] but its a little over my head. Is this the only way to do it?

wrote:
You are using buffered reads and writes I would assume, right? Also, how do you think most programs handle this sort of thing? I don't believe I'm using buffering.
My code looks something like this
//...necessary imports
//then
Scanner inFile = new Scanner (new file("filename1.txt"));
PrintWriter outFile = new PrintWriter ("filename2.txt");
//then stuff like
int x = inFile.hasNextInt();
outFile.println(x);
camickr wrote:If you are changing the data "in place", that is none of the data in the file is shifted, then you can use a RandomAccessFile.
Otherwise, you've been given the answer above.What is RandomAccessFile? Is it what I have a link to? Basically what I do is I write a bunch of numbers to a txt file and then change the numbers I don't need anymore to 0. So say I had 0 1 2 3 4 5 6 7 etc. I would like to to open the txt file and change every second one to 0 so then I'd have only odd numbers and 0s.
I looked at the documentation for RandomAccessFile and it seems like it might be what I need.
Thankyou both for your help so far. I took a java course in high school and they only taught me one way to get data from text files and that is what I just showed you. So maybe this questions are really stupid. lol
Edited by: qw3n on Jun 13, 2009 7:46 PM

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