StructuredMessage Class — spring-boot Architecture

Source Code

core/spring-boot/src/main/java/org/springframework/boot/logging/log4j2/StructuredMessage.java lines 31–66

final class StructuredMessage {

	private static final String JSON2 = "JSON";

	private static final String[] JSON = { JSON2 };

	private StructuredMessage() {
	}

	static Object get(Message message) {
		if (message instanceof MultiFormatStringBuilderFormattable multiFormatMessage
				&& hasJsonFormat(multiFormatMessage)) {
			return WritableJson.of((out) -> formatTo(multiFormatMessage, out));
		}
		return message.getFormattedMessage();
	}

	private static boolean hasJsonFormat(MultiFormatStringBuilderFormattable message) {
		for (String format : message.getFormats()) {
			if (JSON2.equalsIgnoreCase(format)) {
				return true;
			}
		}
		return false;
	}

	private static void formatTo(MultiFormatStringBuilderFormattable message, Appendable out) throws IOException {
		if (out instanceof StringBuilder stringBuilder) {
			message.formatTo(JSON, stringBuilder);
		}
		else {
			out.append(message.getFormattedMessage(JSON));
		}
	}

}