(Java) Overwrite line in .txt file

**CruelCoin** · December 18th, 2013, 09:37 AM

Hi All.

I'm trying to create a counter that will survive the program being closed and reopened.

I need to start with a txt file that has one line in it with 2000 as the text

On running the program, i need this to be overwritten with 1999.
Running again will overwrite with 1998, etc etc.

Any tips on how i could do this?

CC.

**andbin** · December 18th, 2013, 09:55 AM

Originally Posted by CruelCoin

I'm trying to create a counter that will survive the program being closed and reopened.

I need to start with a txt file that has one line in it with 2000 as the text

On running the program, i need this to be overwritten with 1999.
Running again will overwrite with 1998, etc etc.

Any tips on how i could do this?

Updating a file, in the sense to keep the actual content and "pass" over changing only some things is more difficult, especially if it's a text file.
In your case, it's sufficient to recreate the file using any of the standard I/O classes for output.

**CruelCoin** · December 18th, 2013, 10:28 AM

Hi,

Am i correct then in saying that using Filewriter with the same filename will overwrite the existing file? Or would it append?

CC.

**andbin** · December 18th, 2013, 10:34 AM

Originally Posted by CruelCoin

Am i correct then in saying that using Filewriter with the same filename will overwrite the existing file? Or would it append?

FileWriter overwrites (in other words: rewrite from the beginning) the file .... unless you use the constructor with the boolean append parameter so that you can choose.