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javaxmljavabeansxmlbeansxmlmapper

Update partial XML mapping to bean

I need to map an xml file subset of nodes to a Java Bean.

For example map

<data>
    <field1>Value</field1>
    <field2>Value</field2>
    <field3>Value</field3>
    <field4>Value</field4>
    <field5>Value</field5>
</data>

to

public class DataBean {
    private String field2;
    private String field5;
    // ...getter/setter
}

then manipulate the bean and update the source xml file without loosing elements that are not mapped. How can I use to do it? What library?

Thanks for help, Maurizio

Solution

  • Note: I'm the EclipseLink JAXB (MOXy) lead an a member of the JAXB 2 (JSR-222) expert group.

    Below is how this can be done with MOXy's implementation of the JAXB Binder:

    DataBean

    package forum9988170;

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement(name="data")
public class DataBean {

    private String field2;
    private String field5;

    public String getField2() {
        return field2;
    }

    public void setField2(String field2) {
        this.field2 = field2;
    }

    public String getField5() {
        return field5;
    }

    public void setField5(String field5) {
        this.field5 = field5;
    }

}

    jaxb.properties

    To specify MOXy as your JAXB provider you need to add a file named jaxb.properties in the same package as your domain classes with the following entry,

    javax.xml.bind.context.factory=org.eclipse.persistence.jaxb.JAXBContextFactory

    Demo

    package forum9988170;

import java.io.File;
import javax.xml.bind.*;
import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import org.w3c.dom.Document;
import org.w3c.dom.Node;

public class Demo {

    public static void main(String[] args) throws Exception {
        JAXBContext jc = JAXBContext.newInstance(DataBean.class);

        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        DocumentBuilder db = dbf.newDocumentBuilder();
        File xml = new File("src/forum9988170/input.xml");
        Document document = db.parse(xml);

        Binder<Node> binder = jc.createBinder();
        DataBean dataBean = (DataBean) binder.unmarshal(document);
        dataBean.setField2("NEW FIELD 2");
        dataBean.setField5("NEW FIELD 5");
        binder.updateXML(dataBean);

        TransformerFactory tf = TransformerFactory.newInstance();
        Transformer t = tf.newTransformer();
        DOMSource source = new DOMSource(document);
        StreamResult result = new StreamResult(System.out);
        t.transform(source, result);
    }

}

    Output

    <?xml version="1.0" encoding="UTF-8" standalone="no"?>
<data>
    <field1>Value</field1>
    <field2>NEW FIELD 2</field2>
    <field3>Value</field3>
    <field4>Value</field4>
    <field5>NEW FIELD 5</field5>
</data>

    For More Information