core/src/main/java/org/springframework/security/authentication/event/LoggerListener.java
public void onApplicationEvent(AbstractAuthenticationEvent event) {
		if (!logInteractiveAuthenticationSuccessEvents
				&& event instanceof InteractiveAuthenticationSuccessEvent) {
			return;
		}

		if (logger.isWarnEnabled()) {
			final StringBuilder builder = new StringBuilder();
			builder.append("Authentication event ");
			builder.append(ClassUtils.getShortName(event.getClass()));
			builder.append(": ");
			builder.append(event.getAuthentication().getName());
			builder.append("; details: ");
			builder.append(event.getAuthentication().getDetails());

			if (event instanceof AbstractAuthenticationFailureEvent) {
				builder.append("; exception: ");
				builder.append(((AbstractAuthenticationFailureEvent) event)
						.getException().getMessage());
			}

			logger.warn(builder.toString());
		}
	}
public void onApplicationEvent(AbstractAuthenticationEvent event) {
		if (!logInteractiveAuthenticationSuccessEvents
				&& event instanceof InteractiveAuthenticationSuccessEvent) {
			return;
		}

		if (logger.isWarnEnabled()) {
			final StringBuilder builder = new StringBuilder();
			builder.append("Authentication event ");
			builder.append(ClassUtils.getShortName(event.getClass()));
			builder.append(": ");
			builder.append(event.getAuthentication().getName());
			builder.append("; details: ");
			builder.append(event.getAuthentication().getDetails());

			if (event instanceof AbstractAuthenticationFailureEvent) {
				builder.append("; exception: ");
				builder.append(((AbstractAuthenticationFailureEvent) event)
						.getException().getMessage());
			}

			logger.warn(builder.toString());
		}
	}
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