FileEncodingApplicationListener Class — spring-boot Architecture

Source Code

core/spring-boot/src/main/java/org/springframework/boot/context/FileEncodingApplicationListener.java lines 48–80

public class FileEncodingApplicationListener
		implements ApplicationListener<ApplicationEnvironmentPreparedEvent>, Ordered {

	private static final Log logger = LogFactory.getLog(FileEncodingApplicationListener.class);

	@Override
	public int getOrder() {
		return Ordered.LOWEST_PRECEDENCE;
	}

	@Override
	public void onApplicationEvent(ApplicationEnvironmentPreparedEvent event) {
		ConfigurableEnvironment environment = event.getEnvironment();
		String desired = environment.getProperty("spring.mandatory-file-encoding");
		if (desired == null) {
			return;
		}
		String encoding = System.getProperty("file.encoding");
		if (encoding != null && !desired.equalsIgnoreCase(encoding)) {
			if (logger.isErrorEnabled()) {
				logger.error("System property 'file.encoding' is currently '" + encoding + "'. It should be '" + desired
						+ "' (as defined in 'spring.mandatoryFileEncoding').");
				logger.error("Environment variable LANG is '" + System.getenv("LANG")
						+ "'. You could use a locale setting that matches encoding='" + desired + "'.");
				logger.error("Environment variable LC_ALL is '" + System.getenv("LC_ALL")
						+ "'. You could use a locale setting that matches encoding='" + desired + "'.");
			}
			throw new IllegalStateException("The Java Virtual Machine has not been configured to use the "
					+ "desired default character encoding (" + desired + ").");
		}
	}

}