public Builder setTimestampAsNow() {
            //set timestamp based on current time
            DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
            dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
            this.timestamp = dateFormat.format(new Date());
            return this;
        }
Sets the timestamp as the current time in RFC 3339 format.

@return This builder.
smithy-codegen-core/src/main/java/software/amazon/smithy/codegen/core/trace/TraceMetadata.java