or if your #
is always at the beginning of the string:
EDIT:
while((line = rf.readLine()) != null) {
if(line.charAt(0)=='#'){
scan.nextLine(); //use it to suit your need..
//alert the program to prepare for new type of object
//do something..
}else {
split = scan.nextLine().split(", ");
pnumber = Integer.parseInt(split[0]);
name = split[1];
age = Integer.parseInt(split[2]);
thePerson = new Person(name, age, pnumber);
personList.addLast(thePerson);
}
}