/**
* Returns the path of file containing preferences values, as this varies across different
* execution platforms.
*
* @return a string containing the full file path to the preference file, according to execution
* platform.
*/
public final String computePreferenceFilepath() {
_fullFilepath = FileUtils.getPlatformPreferencesPath();
_fullFilepath += getPreferenceFilename();
_logger.debug("Computed preference file path = '{}'.", _fullFilepath);
return _fullFilepath;
}
/**
* Save the preferences state in memory (i.e for the current session) to file.
*
* @param comment comment to be included in the preference file.
* @throws PreferencesException if the preference file could not be written.
*/
public final void saveToFile(final String comment) throws PreferencesException {
// Store current Preference object revision number
setPreference(JMCS_STRUCTURE_VERSION_NUMBER_ID, getJmcsStructureVersionNumber());
setPreference(PREFERENCES_VERSION_NUMBER_ID, getPreferencesVersionNumber());
OutputStream outputFile = null;
try {
outputFile = new BufferedOutputStream(new FileOutputStream(_fullFilepath));
_logger.info("Saving '{}' preference file.", _fullFilepath);
_currentProperties.storeToXML(outputFile, comment);
} catch (IOException ioe) {
throw new PreferencesException("Cannot store preferences to file " + _fullFilepath, ioe);
} finally {
FileUtils.closeStream(outputFile);
}
}
/**
* Load preferences from file if any, or reset to default values and notify listeners.
*
* @warning Any preference value change not yet saved will be LOST.
*/
public final void loadFromFile() {
resetToDefaultPreferences(true);
// Loading preference file
_logger.info("Loading '{}' preference file.", _fullFilepath);
InputStream inputFile = null;
try {
inputFile = new BufferedInputStream(new FileInputStream(_fullFilepath));
} catch (FileNotFoundException fnfe) {
_logger.warn("Cannot load '{}' preference file: ", _fullFilepath, fnfe.getMessage());
}
if (inputFile != null) {
boolean ok = false;
try {
_currentProperties.loadFromXML(inputFile);
ok = true;
} catch (InvalidPropertiesFormatException ipfe) {
_logger.error("Cannot parse '{}' preference file: ", _fullFilepath, ipfe);
} catch (IOException ioe) {
_logger.warn("Cannot load '{}' preference file: ", _fullFilepath, ioe);
} finally {
FileUtils.closeStream(inputFile);
}
if (ok) {
handlePreferenceUpdates();
} else {
// Do nothing just default values will be into the preferences.
_logger.info("Failed loading preference file, so fall back to default values instead.");
resetToDefaultPreferences();
}
}
// Notify all preferences listener of maybe new values coming from file.
triggerObserversNotification();
}