A general comment on your coding style:
Instead of chaining all those constructors and methods in one statement, break them up into separate single steps. I'm not sure what your mess of code does with creating a new DataInputStream object every time around the loop.
The reason the first 'a' is missing is that it was read in the c variable and ignored.
To read Strings from a text file, use a BufferedReader class wrapped around a FileReader object. It has a method that makes it very easy to read lines from a text file.
Another possibility is to use the Scanner class. It has lots of methods to read different data from a file.