How to get rid of empty lines in a file?

It really isn't very sensible to try and do this kind of editing on a text file "in place". If the file is a sensible length you could simply read the whole thing into memory, remove the blank lines, and overwrite the original file.

You may need to give some thought to what happens to the file if the program doesn't complete.

In principal you could map the file into a ByteBuffer (via RandomAccessFile -> FileChanel) and change it in place. You'd tranfer bytes using a read and a write offset into the buffer, deleting is actually less messey than inserting would be. At the end you'd need to truncate the file.

However it would be more efficent to create a new file, then rename the old and new versions so that the new version replaced the old.

malcolmmca at 2007-7-7 17:38:15 >