How to use StaxEventItemReader in Spring Batch for complex xml

Question

Please help me in writing the ItemReader()

    <File>
        <FileDate>05/28/2016</FileDate>
        <RecordCount>75</RecordCount>
        <Transaction>
           <RecordID>1</RecordID>
           <MemberDetails>
               <Id>A2334549</Id>
               <MemberDemoData>
                   <SubID>89890734548557</SubID>
                   <MemberSuffix>01</MemberSuffix>
                   <SSN>XXXXX</SSN>
                   <CategoryCode>B</CategoryCode>
                   <Gender>F</Gender>
                   <LastName>Naaz</LastName>
                   <FirstName>Affu</FirstName>
                   <MiddleInitial>H</MiddleInitial>
                   <BirthDate>04/02/1990</BirthDate>
                   <HICNumber>4567376739A</HICNumber>
                   <PhoneNumber>894567893</PhoneNumber>
                   <ProviderID>09678546</ProviderID>
                   <PCPOverride>N</PCPOverride>
                   <Address>
                       <AddressType>HOME</AddressType>
                       <Address1>2226 Indira nagar RD</Address1>
                       <City>Noida</City>
                       <State>Delhi</State>
                       <Zip>525001</Zip>
                       <County>India</County>
                   </Address>
                   <Address>
                       <AddressType>MAIL</AddressType>
                       <Address1>2226 Indira nagar RD</Address1>
                       <City>Noida</City>
                       <State>Delhi</State>
                       <Zip>525001</Zip>
                       <County>India</County>
                   </Address>
                   <AgentInfo>
                       <MailAgentNo>40</MailAgentNo>
                       <AgentNo>67894</AgentNo>
                   </AgentInfo>
              </MemberDemoData>
              <Package>
                 <Plan>Yu8883</Plan>
                 <PlanId>009</PlanId>
                 <SegmentId>104</SegmentId>
                 <Group>000987666</Group>
                 <SubGroup>B004</SubGroup>
                 <Class>0004</Class>
                 <PartD>
                     <BIN>789034</BIN>
                     <PCN>*******</RxPCN>
                 </PartD>
                 <EffectiveDate>09/01/2016/01/2016</EffectiveDate>
                 <TerminationDate>12/31/2016</TerminationDate>
             </Package>
             <LICSInfo>
                 <SubsidyLevel>100</SubsidyLevel>
                 <CopayCategory>1</CopayCategory>
                 <SubsidyLevelStartDate>08/11/2016</SubsidyLevelStartDate>
             </LICSInfo>
             <MedihealthData>
                    <PartA>
                       <EffectiveDate>02/01/2008</EffectiveDate>
                    </PartA>
                    <PartB>
                       <EffectiveDate>02/01/2008</EffectiveDate>
                    </PartB>
                    <ESignDate>
                       <EffectiveDate>08/16/2016</EffectiveDate>
                    </ESignDate>
            <ElectionPeriod>S</ElectionPeriod>
                    <EnrollmentDate>
                       <EffectiveDate>08/01/2016</EffectiveDate>
                    </EnrollmentDate>
               </MedihealthData>
               <BillingData>
                    <PremiumWithHold>D</PremiumWithHold>
               </BillingData>
           </MemberDetails>
        </Transaction>
        <Transaction>
         -------
        </Transaction>
        <Transaction>
         ------
        </Transaction>
        <Transaction>
         -------
        </Transaction>
    </File>

I have jaxb generated classes for File, Transaction, MemberDetails, MemberDemoData, Address, AgentInfo,Package, PartD, LICSInfo, MedihealthData, PartA, PartB, ESignDate, EnrollmentDate, BillingData

Now in the below ItemReader method in place of "?" what class name should I use exactly. Please help me.

    public ItemReader<?> fileXmlReader(@Value("#{stepExecution}") StepExecution stepExecution) {

            StaxEventItemReader<?> xmlFileReader = new StaxEventItemReader<>();

            xmlFileReader.setResource(new ClassPathResource("/File.xml"));

            xmlFileReader.setFragmentRootElementNames( new String[] {?}); (or )
            xmlFileReader.setFragmentRootElementName(?)

            Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
            marshaller.setClassesToBeBound(?);

            xmlFileReader.setUnmarshaller(marshaller);

            return xmlFileReader;

    }

Answer 1

I found the following solution that could be helpful for others:

@Bean
public StaxEventItemReader<Entity> reader() {

    XStreamMarshaller unmarshaller = new XStreamMarshaller();

    Map<String, Class> aliases = new HashMap<>();
    aliases.put("File", Entity.class);

    unmarshaller.setAliases(aliases);

    StaxEventItemReader<Customer> reader = new StaxEventItemReader<>();

    reader.setResource(new ClassPathResource("/data/file.xml"));
    reader.setFragmentRootElementName("file");
    reader.setUnmarshaller(unmarshaller);


    return reader;
}