public void readFully(byte[] bytes,int start,int len) throws IOException {
  dataInput.readFully(bytes,start,len);
  offset+=len;
  available-=len;
}

public void readFully ( byte [ ] bytes , int start , int len ) throws IOException { dataInput . readFully ( bytes , start , len ) ; offset += len ; available -= len ; }
reads a full byte array completely .
