void attemptToCloseStreams() {
        log("Will now attempt to close any open files.");
        if (inputReader != null) {
            try {
                inputReader.close();
                log("Successfully closed " + inputFilename);
            } catch (IOException e) {
                logError("could not close file for reading: " + inputFilename + "\n" + e.getMessage());
            }
        }
        if (sortedWriter != null) {
            try {
                sortedWriter.close();
                log("Successfully closed " + sortedOutputFilename);
            } catch (IOException e) {
                logError("could not close file for writing: " + sortedOutputFilename + "\n" + e.getMessage());
            }
        }
        if (histogramWriter != null) {
            try {
                histogramWriter.close();
                log("Successfully closed " + histogramOutputFilename);
            } catch (IOException e) {
                logError("could not close file for writing: " + histogramOutputFilename + "\n" + e.getMessage());
            }
        }
    }