how to delete the content of text file without deleting itself

Question

I want to copy the content of file \'A\' to file \'B\'. after the copying is done I want to clear the content of file \'A\' and want to write on it from its beginning. I can

Answer 1

How about below:

File temp = new File("");
if (temp.exists()) {
    RandomAccessFile raf = new RandomAccessFile(temp, "rw");
    raf.setLength(0);
}