code: public void close() throws IOException {
  		if (t1==null || t2==null) {
  			return;
  		}
  		try {
  			if (getOutput().length() > 0) {
  				Files.copy(getOutput().toPath(), output.toPath(), StandardCopyOption.REPLACE_EXISTING);
  			}
  			else if (getInput().length() > 0) {
  				Files.copy(getInput().toPath(), output.toPath(), StandardCopyOption.REPLACE_EXISTING);
  			}
  			else {
  				throw new IOException("Temporary files corrupted.");
  			}
  		} finally {
  			t1.delete();
  			t2.delete();
  			t1 = null;
  			t2 = null;
  		}
  	}
docs: Closes the temporary files and copies the result to the output file.
  Closing the TempFileHandler is a mandatory last step after which no other
  calls to the object should be made.
  
  @throws IOException
  An IOException is thrown if the temporary files have been
  deleted, or are empty.