XML Stream Marshaller

JaxbXmlStreamMarshaller.kt

import jakarta.xml.bind.JAXBContext
import jakarta.xml.bind.JAXBElement
import jakarta.xml.bind.Marshaller
import org.slf4j.Logger
import org.slf4j.LoggerFactory
import java.io.FileOutputStream
import javax.xml.namespace.QName
import javax.xml.stream.XMLOutputFactory
import javax.xml.stream.XMLStreamWriter

object JaxbXmlStreamMarshaller {

    private val logger: Logger = LoggerFactory.getLogger(this::class.java)

    private val caResponseJaxbContext = JAXBContext.newInstance(CorpAction::class.java)

    private val marshaller = caResponseJaxbContext.createMarshaller().also {
        it.setProperty(Marshaller.JAXB_FRAGMENT, true)
    }

    private lateinit var xmlOut: XMLStreamWriter

    fun open(fileName: String) {
        xmlOut = XMLOutputFactory.newFactory().createXMLStreamWriter(FileOutputStream(fileName));
        xmlOut.writeStartDocument();
        xmlOut.writeStartElement("", "CAResponse", "http://www.cstools.broker.com")
    }

    fun write(corpAction: CorpAction) {
        val element: JAXBElement<CorpAction> = JAXBElement<CorpAction>(QName.valueOf(CorpAction::class.simpleName), CorpAction::class.java, corpAction)
        marshaller.marshal(element, xmlOut)
    }

    fun close() {
        xmlOut.writeEndDocument()
        xmlOut.close()
    }
}

JaxbXmlUnmarshaller.kt

import jakarta.xml.bind.JAXBContext
import jakarta.xml.bind.Marshaller
import jakarta.xml.bind.UnmarshalException
import org.slf4j.Logger
import org.slf4j.LoggerFactory
import org.springframework.util.ResourceUtils
import java.io.OutputStream
import java.io.Reader
import javax.xml.XMLConstants
import javax.xml.validation.Schema
import javax.xml.validation.SchemaFactory

object JaxbXmlUnmarshaller {

    private val logger: Logger = LoggerFactory.getLogger(this::class.java)

    private val caResponseJaxbContext = JAXBContext.newInstance(CAResponse::class.java)

    private var caResponseSchema: Schema = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI)
        .newSchema(ResourceUtils.getFile("classpath:xsd/ca_v20230217.xsd"))

    fun unmarshall(reader: Reader): CAResponse {
        val unmarshaller = caResponseJaxbContext.createUnmarshaller()
        unmarshaller.schema = caResponseSchema
        return try {
            unmarshaller.unmarshal(reader) as CAResponse
        } catch (e: UnmarshalException) {
            logger.error("Unable to parse corporate action xml", e)
            throw XmlCorporateActionParsingException(ignorable = false, e.message)
        }
    }

}

Test.kt

    @Test
    fun `generate test data`() {
        // given
        val pathToXml = "corporateactionfiles/minimal/corpaction_CASH_DIVIDEND.xml"
        val parsedXml = parseXml(pathToXml)

        val b = parsedXml.corpAction[0]
        val numOfCustomer = 10_500 * 10
        val numOfCaEvent = 100

        JaxbXmlStreamMarshaller.open("/tmp/ca-large.xml")

        for (i in 1..numOfCaEvent * numOfCustomer) {
            JaxbXmlStreamMarshaller.write(b.also {
                it.id += i % numOfCaEvent
            })
        }
        JaxbXmlStreamMarshaller.close()
    }
    
    /*
    <CAResponse>
        <CorpActon></CorpAction>
        <CorpActon></CorpAction>
        <CorpActon></CorpAction>
        ...
    </CAResponse>
    */
    
    private fun parseXml(pathToXml: String): CAResponse {
        return JaxbXmlUnmarshaller.unmarshall(
            InputStreamReader(
                ByteArrayInputStream(
                    ClassPathResource(pathToXml).inputStream.readAllBytes()
                )
            )
        )
    }