public final void writeName(long name) {
        if (startObject) {
            startObject = false;
        } else {
            writeComma();
        }

        writeInt64(name);
    }
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