public static JSONWriter of() {
        JSONWriter.Context writeContext = new JSONWriter.Context(defaultObjectWriterProvider);
        JSONWriter jsonWriter;
        if (JVM_VERSION == 8) {
            if (FIELD_STRING_VALUE != null && !ANDROID && !OPENJ9) {
                jsonWriter = new JSONWriterUTF16JDK8UF(writeContext);
            } else {
                jsonWriter = new JSONWriterUTF16JDK8(writeContext);
            }
        } else if ((defaultWriterFeatures & OptimizedForAscii.mask) != 0) {
            jsonWriter = ofUTF8(writeContext);
        } else {
            if (FIELD_STRING_VALUE != null && STRING_CODER != null && STRING_VALUE != null) {
                jsonWriter = new JSONWriterUTF16JDK9UF(writeContext);
            } else {
                jsonWriter = new JSONWriterUTF16(writeContext);
            }
        }
        return jsonWriter;
    }
If ReferenceDetection has been set, returns the path of the current object, otherwise returns null
@since 2.0.51
@return the path of the current object
core/src/main/java/com/alibaba/fastjson2/JSONWriter.java