code: private void loadDefaultConfig() {
  		this.configDir = System.getProperty(CONFIG_DIR_SYS_PROP);
  		if (this.configDir == null) {
  			this.configDir = getDefaultConfigDir();
  		}
  		if (this.configDir == null) {
  			throw new AssertionError("eureka.config.dir not specified in " + FALLBACK_CONFIG_FILE);
  		}
  		File configFile = new File(this.configDir, PROPERTIES_FILENAME);
  		if (configFile.exists()) {
  			LOGGER.info("Trying to load default configuration from {}",
  					configFile.getAbsolutePath());
  			InputStream inputStream = null;
  			try {
  				inputStream = new FileInputStream(configFile);
  				this.properties.load(inputStream);
  				inputStream.close();
  				inputStream = null;
  			} catch (IOException ex) {
  				LOGGER.error("Error reading application.properties file {}: {}. "
  						+ "Built-in defaults will be used, some "
  						+ "of which are unlikely to be what you want.",
  						configFile.getAbsolutePath(), ex.getMessage());
  			} finally {
  				if (inputStream != null) {
  					try {
  						inputStream.close();
  					} catch (IOException ignore) {
  					}
  				}
  			}
  		} else {
  			LOGGER.warn("No configuration file found at {}. "
  					+ "Built-in defaults will be used, some "
  					+ "of which are unlikely to be what you want.",
  					configFile.getAbsolutePath());
  		}
  	}
docs: Loads the application configuration.
  
  There are two potential sources of application configuration. The
  fallback configuration should always be there. The default configuration
  directory, <code>/etc/ec-cas-server</code>, may optionally have an
  application.properties file within it that overrides the fallback
  configuration for each configuration property that is specified. The
  <code>eureka.config.dir</code> system property allows specifying an
  alternative configuration directory.