wat u are asking for can easily done...using files...if u could go through the
documentation ...i wl give u a hint...try using random access files

The following code creates a RandomAccessFile to read the file  named
farrago.txt:
new RandomAccessFile("farrago.txt", "r");
And this one opens the same file for both reading and writing:
new RandomAccessFile("farrago.txt", "rw");