HessianSerialization.groovy

import com.caucho.hessian.io.Deflation
import com.caucho.hessian.io.Hessian2Input
import com.caucho.hessian.io.Hessian2Output
import groovy.transform.Canonical
import spock.lang.Specification

import java.time.LocalDate

@Canonical
class Person implements Serializable {
    String name
    String birthDate
    String phone
}

class HessianSpec extends Specification {

    def deflation = new Deflation()

    def "Serialize deserialize"() {
        given:
        def someInt = 123
        def persons = [
                new Person("John", LocalDate.of(1983, 1, 9).toString(), '3827857'),
                new Person("David", LocalDate.of(1974, 6, 16).toString(), '846726'),
        ]
        def data = serializeSomeData(someInt, persons)

        when:
        def (outInt, outPerson) = deserialize(data)

        then:
        outInt && outPerson
        persons == outPerson
    }

    def deserialize(byte[] bytes) {
        def inputStream = new ByteArrayInputStream(bytes)
        def hi = new Hessian2Input(inputStream)

        def unwrappedHI = deflation.unwrap(hi)

        unwrappedHI.startMessage()

        def outInt = unwrappedHI.readInt()
        def resultList = []
        def start = unwrappedHI.readListStart()
        def object = unwrappedHI.readObject()
        resultList << object
        unwrappedHI.readListEnd()

        unwrappedHI.completeMessage()
        unwrappedHI.close()
        inputStream.close()

        [outInt, resultList]
    }

    def serializeSomeData(int i, List<Person> persons) {

        def outStream = new ByteArrayOutputStream()
        def ho = new Hessian2Output(outStream)

        def wrapedHO = deflation.wrap(ho)

        wrapedHO.startMessage()

        wrapedHO.writeInt i

//        ho.writeListBegin(persons.size(), nameC)
        wrapedHO.writeListBegin(persons.size(), Person.canonicalName)
        persons.each { wrapedHO.writeObject it }
        wrapedHO.writeListEnd()

        wrapedHO.completeMessage()
        wrapedHO.close()
        outStream.toByteArray()
    }
}