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How to JAXB-marshall JavaFX Property classes when class is XmlAccessType.NONE?

I would like a Java class containing JavaFX Property objects (DoubleProperty, StringProperty, IntegerProperty) to be written into an XML file using JAXB's marshall() method call. However, this class contains lots of data that I do not want written into the XML. This class is expected to be modified by developers often, so I prefer to mark the class "#XmlAccessorType(XmlAccessType.NONE)" and then add #XmlElement tags to anything I want written into the XML (so a developer doesn't add some new member variables into this class and then accidentally alter the XML file's format).
I see examples such as http://blog.bdoughan.com/2010/11/jaxb-and-inheritance-using-xsitype.html, but none of them have "#XmlAccessorType(XmlAccessType.NONE) " for their main class. When I add this tag to my class, I get either runtime Exceptions (because JAXB cannot create a new object) or an empty XML tag in the output (because JAXB created a default object of ome kind but didn't put the desired value into it). I have experimentes with dozens of #Xml* tag combinations but I cannot find one that works.
Note that I cannot annotate any of the DoubleProperty/SimpleDoubleProperty classes because they are part of the standard Java API.
Here is a code example, demonstrating the troubles with getting the bankAccountBalance property into the XML file. (you can ignore the other data - I started with Blaise Doughan's code as a starting-point for this example).
package Demo2;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.SimpleDoubleProperty;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlElementRef;
import javax.xml.bind.annotation.XmlRootElement;
public class Demo2 {
public static void main(String[] args) throws Exception {
Customer customer = new Customer();
Address address = new Address();
address.setStreet("1 A Street");
customer.setContactInfo(address);
customer.setBankAccountBalance(123.45);
JAXBContext jc = JAXBContext.newInstance(Customer.class, Address.class, PhoneNumber.class);
Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
marshaller.marshal(customer, System.out);
}
}
abstract class ContactInfo {
}
class Address extends ContactInfo {
private String street;
public String getStreet() {
return street;
}
public void setStreet(String street) {
this.street = street;
}
}
class PhoneNumber extends ContactInfo {
}
#XmlRootElement
#XmlAccessorType(XmlAccessType.NONE)
class Customer {
#XmlElement
private ContactInfo contactInfo;
// This tag runs OK but always outputs an empty XML tag ("<bankAccountBalance/>") regardless of the real value.
// #XmlElement
// This tag causes the following error:
// Exception in thread "main" com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException: 1 counts of IllegalAnnotationExceptions
// Invalid #XmlElementRef : Type "class javafx.beans.property.DoubleProperty" or any of its subclasses are not known to this context.
// #XmlElementRef
// This tag causes the following error:
// Exception in thread "main" com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException: 1 counts of IllegalAnnotationExceptions
// Invalid #XmlElementRef : Type "class javafx.beans.property.SimpleDoubleProperty" or any of its subclasses are not known to this context.
// #XmlElementRef(type=SimpleDoubleProperty.class)
private DoubleProperty bankAccountBalance;
public Customer() {
bankAccountBalance = new SimpleDoubleProperty(0);
}
public ContactInfo getContactInfo() {
return contactInfo;
}
public void setContactInfo(ContactInfo contactInfo) {
this.contactInfo = contactInfo;
}
public double getBankAccountBalance() {
return bankAccountBalance.get();
}
public void setBankAccountBalance(double bankAccountBalance) {
this.bankAccountBalance.set(bankAccountBalance);
}
}

Simply annotate the getter and not the DoubleProperty field, which nicely bypasses the javafx class. Don't forget to setValue so you see the result.
#XmlElement
public double getBankAccountBalance() {
return bankAccountBalance.get();
}

any way to convert xml to object in java?

I am trying to use a XML and access to all fields and data on an easy way, so, I decided to use JaxB , but I have no idea how to create all the classes for the objects, I tried manually like this.
#XmlRootElement(name = "Response")
public class Response {
#XmlElement(ns = "SignatureValue")
String signatureValue;
}
But I get an error on #XmlElement saying the annotation is disallowed for this location...
I checked other posts and they work great if I have something like Hellw but doesnt work with more complex formats, an example of first part of mine is like this
<?xml version="1.0" encoding="UTF-8"?><DTE xsi:noNamespaceSchemaLocation="http://www.myurl/.xsd" xmlns:gs1="urn:ean.ucc:pay:2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
any idea how to do all this??
Thanks in advance
EDIT:
I forgot to say, the XML is actually a String with the entire XML.

The #XmlElement annotation is valid on a field. If you have a corresponding property then you should annotate the class with #XmlAccessorType(XmlAccessType.FIELD) to avoid a duplicate mapping exception.
Java Model
Annotating the Field
#XmlRootElement(name = "Response")
#XmlAccessorType(XmlAccessType.FIELD)
public class Response {
#XmlElement(name = "SignatureValue")
String signatureValue;
public String getSignatureValue() {
return signatureValue;
}
public void setSignatureValue(String signatureValue) {
this.signatureValue = signatureValue;
}
}
Annotating the Property
import javax.xml.bind.annotation.*;
#XmlRootElement(name = "Response")
public class Response {
String signatureValue;
#XmlElement(name = "SignatureValue")
public String getSignatureValue() {
return signatureValue;
}
public void setSignatureValue(String signatureValue) {
this.signatureValue = signatureValue;
}
}
For More Information
http://blog.bdoughan.com/2011/06/using-jaxbs-xmlaccessortype-to.html
Demo Code
Below is some demo code that reads/writes the XML corresponding to your Response class.
Demo
import java.io.File;
import javax.xml.bind.*;
public class Demo {
public static void main(String[] args) throws Exception {
JAXBContext jc = JAXBContext.newInstance(Response.class);
Unmarshaller unmarshaller = jc.createUnmarshaller();
File xml = new File("src/forum19713886/input.xml");
Response response = (Response) unmarshaller.unmarshal(xml);
Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
marshaller.marshal(response, System.out);
}
}
input.xml/Output
<?xml version="1.0" encoding="UTF-8"?>
<Response>
<SignatureValue>Hello World</SignatureValue>
</Response>

Mapping XML Entities to Java Objects

I am quite sure, this is one of the many duplicated questions around XML to Java Object conversions.
But I started this thread since I couldn't find simpler or looking for simpler solution.
I have an xsd [Infact I am designing it] and xml.
I would like to auto-map the xml data to Java beans as per mapping
<tns:SummaryCart xmlns:tns="SummaryCart" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="SummaryCart.xsd">
<SummaryElement type="test">
<order>1</order>
<id>A</id>
<displayName>A</displayName>
<subElements>
<order>1</order>
<id>Preactivation</id>
<displayName>Preactivation</displayName>
</subElements>
<maxlines>1</maxlines>
</SummaryElement>
</tns:SummaryCart>
Now my Java classes will be
public class SummaryCart{
private List<SummaryElement> summaryElementList;
}
public class SummaryElement {
private int order;
private String id;
private String displayName;
private String property;
private List<SummaryElement> subElements;
private int maxlines;
private String type;
}
Is there any simple tool/framework which can auto-map the data from XML to Java beans [MUST support attributes/element mapping]. Tutorial will be good.
Btw, I am using Spring framework, if spring-oxm advantage is taken, its welcome.

Below is how you could map your object to XML using JAXB (JSR-222). An implementation is included in the JDK/JRE starting with Java SE 6. JAXB is supported by Spring (see section 8.5: http://static.springsource.org/spring-ws/site/reference/html/oxm.html)
SummaryCart
import java.util.List;
import javax.xml.bind.annotation.*;
#XmlRootElement(name="SummaryCart", namespace="SummaryCart")
#XmlAccessorType(XmlAccessType.FIELD)
public class SummaryCart{
#XmlElement(name="SummaryElement")
private List<SummaryElement> summaryElementList;
}
SummaryElement
import java.util.List;
import javax.xml.bind.annotation.*;
#XmlAccessorType(XmlAccessType.FIELD)
public class SummaryElement {
private int order;
private String id;
private String displayName;
private String property;
private List<SummaryElement> subElements;
private int maxlines;
#XmlAttribute
private String type;
}
Demo
import java.io.File;
import javax.xml.bind.*;
public class Demo {
public static void main(String[] args) throws Exception {
JAXBContext jc = JAXBContext.newInstance(SummaryCart.class);
Unmarshaller unmarshaller = jc.createUnmarshaller();
File xml = new File("src/forum15881876/input.xml");
SummaryCart sc = (SummaryCart) unmarshaller.unmarshal(xml);
Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
marshaller.setProperty(Marshaller.JAXB_SCHEMA_LOCATION, "SummaryCart.xsd");
marshaller.marshal(sc, System.out);
}
}
input.xml/Output
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ns2:SummaryCart xmlns:ns2="SummaryCart" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="SummaryCart.xsd">
<SummaryElement type="test">
<order>1</order>
<id>A</id>
<displayName>A</displayName>
<subElements>
<order>1</order>
<id>Preactivation</id>
<displayName>Preactivation</displayName>
<maxlines>0</maxlines>
</subElements>
<maxlines>1</maxlines>
</SummaryElement>
</ns2:SummaryCart>

Basically you want to unmarshal your XML. Here's a detailed tutorial that describes how to use the JAXB xjc command to generate a Java class from XML Schema. A maven xjc plugin is also available for your convenience.

Is it possible to programmatically configure JAXB?

Say I have two JavaBeans Person and Address.
If I create a list of Person objects, I'd like to marshal to something like this:
<persons>
<person>...</person>
</persons>
It's possible to use the technique described here:
Using JAXB to unmarshal/marshal a List<String>
By annotating JaxbList with #XmlRootElement(name = "persons") and #XmlElement(name = "person"), then it's possible to marshal to the XML above.
But, it'd be nice to be able to reuse the same JaxbList<T> class to also marshal a list of Address objects. And in reality, I will have many other types of beans. I can go with something like:
<list>
<item xsi:type="person" xmlns:xsi="http://www.w2.org/2001/XmlSchema-instance"></item>
</list>
But, ideally, it'd be nice to have it replace "list" with the plural version of class name and "item" with the class name.
So, is it possible to programmatically configure the JaxbContext or something during runtime and essentially set the value of the name inside #XmlRootElement and #XmlElement?
Or any other way to get this working without having to write a separate implementation of JaxbList for every bean type? Maybe XmlJavaTypeAdapter can achieve this sort of thing?
Update
#Blaise Doughan's solution accepted below works great. For my use case, I needed to go straight from Java object to XML, here's what worked (note this is not my full implementation, it's sort of just pseudo code for demonstration):
//JAXBContext is thread safe and so create it in constructor or
//setter or wherever:
...
JAXBContext jc = JAXBContext.newInstance(Wrapper.class, clazz);
...
public String marshal(List<T> things, Class clazz) {
//configure JAXB and marshaller
Marshaller m = jc.createMarshaller();
m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
//Create wrapper based on generic list of objects
Wrapper<T> wrapper = new Wrapper<T>(things);
JAXBElement<Wrapper> wrapperJAXBElement = new JAXBElement<Wrapper>(new QName(clazz.getSimpleName().toLowerCase()+"s"), Wrapper.class, wrapper);
StringWriter result = new StringWriter();
//marshal!
m.marshal(wrapperJAXBElement, result);
return result.toString();
}

You could create a generic Wrapper object like the following:
Wrapper
You could create a generic wrapper class with a List property annotated with #XmlAnyElement(lax=true). The type of the object used to populate this list will be based on its root element (see: http://blog.bdoughan.com/2010/08/using-xmlanyelement-to-build-generic.html).
package forum13272288;
import java.util.*;
import javax.xml.bind.annotation.XmlAnyElement;
public class Wrapper<T> {
private List<T> items = new ArrayList<T>();
#XmlAnyElement(lax=true)
public List<T> getItems() {
return items;
}
}
Address
You will need to annotate the possible contents of the list with #XmlRootElement.
package forum13272288;
import javax.xml.bind.annotation.XmlRootElement;
#XmlRootElement
public class Address {
}
Person
package forum13272288;
import javax.xml.bind.annotation.XmlRootElement;
#XmlRootElement
public class Person {
}
Demo
The demo code below demonstrates how to use the Wrapper class. Since the root element can be different you will need to specify that you want to unmarshal to the wrapper class. Alternatively you could leverage the #XmlElementDecl annotation to associate multiple root elements with the wrapper class (see: http://blog.bdoughan.com/2012/07/jaxb-and-root-elements.html).
package forum13272288;
import javax.xml.bind.*;
import javax.xml.transform.stream.StreamSource;
public class Demo {
public static void main(String[] args) throws Exception {
JAXBContext jc = JAXBContext.newInstance(Wrapper.class, Person.class, Address.class);
Unmarshaller unmarshaller = jc.createUnmarshaller();
Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
StreamSource personsXML = new StreamSource("src/forum13272288/persons.xml");
JAXBElement<Wrapper> wrapper1 = unmarshaller.unmarshal(personsXML, Wrapper.class);
marshaller.marshal(wrapper1, System.out);
StreamSource addressesXML = new StreamSource("src/forum13272288/addresses.xml");
JAXBElement<Wrapper> wrapper2 = unmarshaller.unmarshal(addressesXML, Wrapper.class);
marshaller.marshal(wrapper2, System.out);
}
}
Output
Below is the output from running the demo code. The files persons.xml and addresses.xml look just like there corresponding output.
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<persons>
<person/>
<person/>
</persons>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<addresses>
<address/>
<address/>
</addresses>
For More Information
http://blog.bdoughan.com/2012/11/creating-generic-list-wrapper-in-jaxb.html

JAXB Adding attributes to a XmlElement for simple data types

I want to add some attributes to Xml Elements using JAXB when marshalling from JavaBeans. The Xml Elements are simple data types like String. So I do not want to create new Classes. For example, a desired output would be:
<notifications>
<date>04/20/2011</date>
<subject creditcard_num="22678" checknum="8904">Credit Card Charge Back</subject>
<body payment_amount="34.00" return_status="charged back">some text</body>
</notifications
I do not want to define subject and body as separate classes.
-Anand

My solution require defining a class for subject and body, but the desired output will be as requested
I use #XmlValue for the message and #XmlAttribute for the attributes
#Test
public void testAll() throws JAXBException
{
String msg = "<notifications><date>04/20/2011</date><subject creditcard_num='22678' checknum='8904'>Credit Card Charge Back</subject><body payment_amount='34.00' return_status='charged back'>some text</body></notifications>";
Notifications tested = (Notifications) JAXBContext.newInstance(Notifications.class).createUnmarshaller().unmarshal(new StringReader(msg));
assertEquals("Credit Card Charge Back",tested.subject.value);
assertEquals("8904",tested.subject.checknum);
assertEquals("22678",tested.subject.creditcard_num);
}
#XmlRootElement
public static class Notifications{
public String date;
public Subject subject;
}
public static class Subject
{
#XmlValue
public String value;
#XmlAttribute(name="creditcard_num")
public String creditcard_num;
#XmlAttribute(name="checknum")
public String checknum;
}
NOTE:I only wrote the subject part, I wonder if using #XmlPath can be used to remove the need for different classes

You could use EclipseLink JAXB (MOXy)'s #XmlPath annotation to solve this problem (I'm the MOXy tech lead):
Notifications
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlRootElement;
import org.eclipse.persistence.oxm.annotations.XmlPath;
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
public class Notifications {
private String date;
#XmlPath("subject/#creditcard_num")
private String creditcardNum;
#XmlPath("subject/#checknum")
private String checknum;
private String subject;
#XmlPath("body/#payment_amount")
private String paymentAmount;
#XmlPath("body/#return_status")
private String returnStatus;
private String body;
}
jaxb.properties
To use MOXy as your JAXB implementation you need to put a file named jaxb.properties in the same package as your model classes with the following entry:
javax.xml.bind.context.factory=org.eclipse.persistence.jaxb.JAXBContextFactory
Demo
import java.io.File;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
public class Demo {
public static void main(String[] args) throws Exception {
JAXBContext jc = JAXBContext.newInstance(Notifications.class);
Unmarshaller unmarshaller = jc.createUnmarshaller();
Notifications notifications = (Notifications) unmarshaller.unmarshal(new File("input.xml"));
Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
marshaller.marshal(notifications, System.out);
}
}
For More Information:
http://bdoughan.blogspot.com/2010/07/xpath-based-mapping.html
http://bdoughan.blogspot.com/2010/09/xpath-based-mapping-geocode-example.html
http://bdoughan.blogspot.com/2011/03/map-to-element-based-on-attribute-value.html