mvvmfx-validation/src/main/java/de/saxsys/mvvmfx/utils/validation/ValidationStatus.java
public Optional<ValidationMessage> getHighestMessage() {
		final Optional<ValidationMessage> error = getMessages().stream()
				.filter(message -> message.getSeverity().equals(Severity.ERROR))
				.findFirst();
		
		if (error.isPresent()) {
			return error;
		} else {
			final Optional<ValidationMessage> warning = getMessages().stream()
					.filter(message -> message.getSeverity().equals(Severity.WARNING))
					.findFirst();
			
			return warning;
		}
	}
public Optional<ValidationMessage> getHighestMessage() {
		final Optional<ValidationMessage> error = getMessages().stream()
				.filter(message -> message.getSeverity().equals(Severity.ERROR))
				.findFirst();
		
		if (error.isPresent()) {
			return error;
		} else {
			final Optional<ValidationMessage> warning = getMessages().stream()
					.filter(message -> message.getSeverity().equals(Severity.WARNING))
					.findFirst();
			
			return warning;
		}
	}
Returns the message with the highest priority using the following algorithm: - if there are messages with
{@link Severity#ERROR}, take the first one. - otherwise, if there are messages with {@link Severity#WARNING},
take the first one. - otherwise, an empty Optional is returned.

@return an Optional containing the ValidationMessage or an empty Optional.