public void processElement(OutputStream outputStream, Object element) throws IOException {
        if (canProcess(element)) {
            process(outputStream, element);
        } else {
            if (next != null) {
                this.next.processElement(outputStream, element);
            }
        }
    }
Wraps {@link Serializer#process(java.io.OutputStream, Object)} and calls next serializer in chain.

@param outputStream the output stream.
@param element      the element to process.
@throws IOException IOException in case of IO error.
src/main/java/spark/serialization/Serializer.java