code: public static String createRandomData(int rows, int rowLength, boolean skipTrailingNewline) {
          Random random = new Random(System.currentTimeMillis());
          StringBuilder strb = new StringBuilder();
          for(int i=0; i<rows; i++) {
              for(int j=0; j<rowLength; j++) {
                  strb.append((char)(((int)'a') + random.nextFloat() * 25));
              }
              if(skipTrailingNewline || i<rows) {
                  strb.append("\n");
              }
          }
          return strb.toString();
      }
docs: This method creates test data containing letters between a-z
  @param rows how many rows of data to create
  @param rowLength how many characters per row
  @param skipTrailingNewline if true then a trailing newline is always added
  @return <code>String</code> contain all random data