SystemStatusListener Class — spring-boot Architecture

Source Code

core/spring-boot/src/main/java/org/springframework/boot/logging/logback/SystemStatusListener.java lines 39–92

final class SystemStatusListener extends OnConsoleStatusListener {

	private static final long RETROSPECTIVE_THRESHOLD = 300;

	private final boolean debug;

	private SystemStatusListener(boolean debug) {
		this.debug = debug;
		setResetResistant(false);
		setRetrospective(0);
	}

	@Override
	public void start() {
		super.start();
		retrospectivePrint();
	}

	private void retrospectivePrint() {
		if (this.context == null) {
			return;
		}
		long now = System.currentTimeMillis();
		List<Status> statusList = this.context.getStatusManager().getCopyOfStatusList();
		statusList.stream()
			.filter((status) -> getElapsedTime(status, now) < RETROSPECTIVE_THRESHOLD)
			.forEach(this::addStatusEvent);
	}

	@Override
	public void addStatusEvent(Status status) {
		if (this.debug || status.getLevel() >= Status.WARN) {
			super.addStatusEvent(status);
		}
	}

	@Override
	protected PrintStream getPrintStream() {
		return (!this.debug) ? System.err : System.out;
	}

	private static long getElapsedTime(Status status, long now) {
		return now - status.getTimestamp();
	}

	static void addTo(LoggerContext loggerContext) {
		addTo(loggerContext, false);
	}

	static void addTo(LoggerContext loggerContext, boolean debug) {
		StatusListenerConfigHelper.addOnConsoleListenerInstance(loggerContext, new SystemStatusListener(debug));
	}

}