public LogFormatter build() {
        final ObjectMapper objectMapper = this.objectMapper;
        final HeadersSanitizer<JsonNode> defaultHeadersSanitizer =
                defaultHeadersSanitizer(objectMapper);
        final BiFunction<? super RequestContext, Object, JsonNode> defaultContentSanitizer =
                defaultSanitizer(objectMapper);
        return new JsonLogFormatter(
                firstNonNull(requestHeadersSanitizer(), HeadersSanitizer.ofJson()),
                firstNonNull(responseHeadersSanitizer(), HeadersSanitizer.ofJson()),
                firstNonNull(requestTrailersSanitizer(), defaultHeadersSanitizer),
                firstNonNull(responseTrailersSanitizer(), defaultHeadersSanitizer),
                firstNonNull(requestContentSanitizer(), defaultContentSanitizer),
                firstNonNull(responseContentSanitizer(), defaultContentSanitizer),
                objectMapper);
    }
Returns a newly-created JSON {@link LogFormatter} based on the properties of this builder.
core/src/main/java/com/linecorp/armeria/common/logging/JsonLogFormatterBuilder.java