PrintWriter pw = new PrintWriter(new FileOutputStream( new File("persons.txt"), true /* append = true */));

The true is the append mode flag. Also check if you're using

pw.append(p.toString()); pw.append("sdf");

http://stackoverflow.com/questions/8210616/printwriter-append-method-not-appending

PrintWriter pw = new PrintWriter(new FileOutputStream( new File("persons.txt"), true /* append = true */));

The true is the append mode flag. Also check if you're using

pw.append(p.toString()); pw.append("sdf");

https://stackoverflow.com/questions/8210616/printwriter-append-method-not-appending