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How to use setters in JAXB collections unmarshalling

I wan't to deserialize XML to my POJO but something doing wrong...
My POJO class:
#Builder
#ToString
#AllArgsConstructor
#NoArgsConstructor
#XmlRootElement(name="taxi")
#XmlAccessorType(XmlAccessType.PROPERTY)
#XmlType(propOrder = {"id", "name", "phone", "citiesId"})
public class TaxiEntity {
#Getter #Setter
private Integer id;
#Getter #Setter
private String name;
#Getter #Setter
private String phone;
#Singular("city")
private Set<Integer> citiesId = new HashSet<>();
#XmlElementWrapper(name="cities_id")
#XmlElement(name="city_id")
public void setCitiesId(Set<Integer> citiesId) {
System.out.println("setCitiesId()");
this.citiesId = citiesId;
}
public Set<Integer> getCitiesId() {
System.out.println("getCitiesId()");
return new HashSet<>(citiesId);
}
}
Marshalling example:
JAXBContext context = JAXBContext.newInstance(TaxiEntity.class);
TaxiEntity entity = TaxiEntity.builder().
id(5).
name("my city").
phone("12345678").
city(1).
city(5).
build();
Marshaller marshaller = context.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
marshaller.marshal(entity, new File("entity.xml"));
XML output:
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<taxi>
<id>5</id>
<name>my city</name>
<phone>12345678</phone>
<cities_id>
<city_id>1</city_id>
<city_id>5</city_id>
</cities_id>
</taxi>
Unmarshalling example:
JAXBContext context = JAXBContext.newInstance(TaxiEntity.class);
Unmarshaller unmarshaller = context.createUnmarshaller();
TaxiEntity entity = (TaxiEntity) unmarshaller.unmarshal(new File("entity.xml"));
System.out.println(entity);
Console output:
getCitiesId()
getCitiesId()
TaxiEntity(id=5, name=my city, phone=12345678, citiesId=[])
Process finished with exit code 0
As you can see, citiesId is empty.
It happens because JAXB unmarshalling calling the getter (copy of field in my case)
and trying to set values into a copy of collection.
How to make it create a collection and set it via setter?
P.S. In my real bussiness object, i have collect IDs in getter from DB entities, and cannot return collection in getter.
Thanks!

---- Edited last time -----
import java.io.File;
import java.util.Set;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlElementWrapper;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlType;
import lombok.Builder;
import lombok.Singular;
import lombok.ToString;
#Builder
#ToString
#XmlRootElement(name = "taxi")
#XmlType(name="taxi", propOrder = { "id", "name", "phone", "citiesId" })
public class TaxiEntity {
private Integer id;
private String name;
private String phone;
#Singular("city")
private Set<Integer> citiesId;
public TaxiEntity() {
}
public TaxiEntity(Integer id, String name, String phone, Set<Integer> citiesId) {
System.out.println("Hello");
this.id = id;
this.name = name;
this.phone = phone;
this.citiesId = citiesId;
}
#XmlElementWrapper(name = "cities_id")
#XmlElement(name = "city_id")
public void setCitiesId(Set<Integer> citiesId) {
System.out.println("I should be calling during deserialization" + citiesId);
this.citiesId = citiesId;
}
#XmlElement
public void setId(Integer id) {
this.id = id;
}
#XmlElement
public void setName(String name) {
this.name = name;
}
#XmlElement
public void setPhone(String phone) {
this.phone = phone;
}
public Integer getId() {
return id;
}
public String getName() {
return name;
}
public String getPhone() {
return phone;
}
public Set<Integer> getCitiesId() {
System.out.println("Calling getter " + this.citiesId);
return citiesId;
}
public static void main(String[] args) {
try {
JAXBContext context = JAXBContext.newInstance(TaxiEntity.class);
Marshaller marshaller = context.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
Unmarshaller unmarshaller = context.createUnmarshaller();
TaxiEntity entity = TaxiEntity.builder().id(5).name("my city").phone("12345678").city(1).city(5).build();
marshaller.marshal(entity, new File("C:/whee/entity.xml"));
System.out.println("Unmarshalling now ------");
TaxiEntity taxEntityWithSettersGetters = (TaxiEntity) unmarshaller.unmarshal(new File("C:/whee/entity.xml"));
System.out.println(taxEntityWithSettersGetters);
} catch (Exception e) {
e.printStackTrace();
}
}
Printout:
Hello
Calling getter [1, 5]
Unmarshalling now ------
Calling getter null
I should be calling during deserialization[]
Calling getter [1, 5]
TaxiEntity(id=5, name=my city, phone=12345678, citiesId=[1, 5])
During unmarshalling JAXB checks if your collection is null, if it is (It will call the setter for the first time to initialize it to empty), and you can see that in the log.
However, afterwards, it will use its internal logic to populate the collection (SET), initialize its type (New Set)*by using the Setter you have, and use the Set.add(xyz); to add (1), then (5).
The JAXB Logic invoked is found in class:
public abstract class Lister<BeanT,PropT,ItemT,PackT> {
//startPacking is calling to initialize the collection Set so it is empty
public T startPacking(BeanT bean, Accessor<BeanT, T> acc) throws AccessorException {
T collection = acc.get(bean);
if(collection==null) {
collection = ClassFactory.create(implClass);
if(!acc.isAdapted())
acc.set(bean,collection);
}
collection.clear();
return collection;
}
//Right way, this gets called afterwards (Before any of your TaxiEntity logic), to do addToPack(1), addToPack(5), <--- Now your Set has [1,5]
public void addToPack(T collection, Object o) {
collection.add(o);
}
Then, you see in the log, it calls getCitiesIds(), and you will see magically it has [1,5]
Its the way JAXB works with Collections. All other elements, their proper Setters are called.
See, JAXB does not call Setter method
You need to think of a different way of doing it, rather than dependending on the getter/setter. It did its job of unmarshalling the object from the XML file, the rest of the logic could be written in an external method.

How to avoid root element annotation while marshalling in JAXB?

I want to store my object data to XML. Below code spinets will show the example of model class.
Class Model
{
#XmlElement
private int id;
#XmlElement
Private string name;
}
I will have multiple model objects which will be stored in some list as below
#XmlRootElement
Class ModelWrapper
{
#XmlElement
#XmlJavaTypeAdapter(value = ListAdapter.class, type = List.class)
List<model> list;
public setlist(List<model>list)
{
//setting list
}
public List<model> getlist()
{
return list
}
}
Now if I marshall this using JAXB, something like this will be produced:
<Modelwrapper>
<List>
......
......
</List>
</Modelwrapper>
I want to avoid one of the root may be list or Modelwrapper.
Is there any way to do it?

In this way your xml will be
<ModelWrapper>
<model>
......
</model>
<model>
......
</model>
</ModelWrapper>
ModelWrapper.java
#XmlRootElement
public class ModelWrapper {
#XmlElement(name = "model")
protected List<Model> list;
Test
ModelWrapper.java
import java.util.List;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlType;
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "ModelWrapper", propOrder = {
"list"
})
public class ModelWrapper {
#XmlElement(name = "model")
private List<Model> list;
public List<Model> getList() {
return list;
}
public void setList(List<Model> list) {
this.list = list;
}
}
Model.java
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlType;
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "Model", propOrder = {
"id","name"
})
public class Model {
#XmlElement
private int id;
#XmlElement
private String name;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Main.java
import java.util.ArrayList;
import java.util.List;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
public class Main {
public static void main(String[] args) throws JAXBException {
JAXBContext jc = JAXBContext.newInstance(ModelWrapper.class);
ModelWrapper mw = new ModelWrapper();
List<Model> list = new ArrayList<Model>();
Model m = new Model();
m.setId(1);
m.setName("model1");
list.add(m);
m = new Model();
m.setId(1);
m.setName("model2");
list.add(m);
mw.setList(list);
Marshaller mar = jc.createMarshaller();
mar.marshal(mw, System.out);
}
}
Output
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<modelWrapper>
<model>
<id>1</id>
<name>model1</name>
</model>
<model>
<id>1</id>
<name>model2</name>
</model>
</modelWrapper>

Make custom xml from javabean

I wants to make xml from javabean like below:
<tag2>message</tag2>
<tag3>message</tag3>
<tag4 id='UNIQUE MT ID 1'>MOBILE No.</tag4>
I tried below code in javabean:
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "name", propOrder = {"tag2", "tag3", "tag4"})
public class newBean {
#XmlElement(required = true)
private List<String> tag2;
#XmlElement(required = true)
private List<String> tag3;
#XmlElement(required = true)
private List<String> tag4;
#XmlPath("tag4/#id")
private List<String> id;
public List<String> getTag2() {
return tag2;
}
public void setTag2(List<String> tag2) {
this.tag2 = tag2;
}
public List<String> gettag4() {
return tag4;
}
public void settag4(List<String> tag4) {
this.tag4 = tag4;
}
public List<String> getId() {
return id;
}
public void setId(List<String> identifier) {
this.id = identifier;
}
public List<String> gettag3() {
return tag3;
}
public void settag3(List<String> tag3) {
this.tag3 = tag3;
}
}
I am getting below error:
Errorcom.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException: 1 counts of IllegalAnnotationExceptions
Property id is present but not specified in #XmlType.propOrder
this problem is related to the following location:
at private java.util.List model.newBean.id
at model.newBean
Please help me.I am using #XmlPath tag and generating error.I searched alot and found that #XmlPath usage is same as above i used but still getting error.

Note: I'm the EclipseLink JAXB (MOXy) lead and a member of the JAXB (JSR-222) expert group.
About #XmlPath
#XmlPath is a EclipseLink JAXB (MOXy) extension and requires that you are using MOXy as your JAXB provider:
http://blog.bdoughan.com/2010/07/xpath-based-mapping.html
http://blog.bdoughan.com/2011/05/specifying-eclipselink-moxy-as-your.html
Valid Use Case #1
import javax.xml.bind.annotation.*;
import org.eclipse.persistence.oxm.annotations.XmlPath;
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "name", propOrder = { "tag4", "id" })
public class newBean {
#XmlElement(required=true)
String tag4;
#XmlPath("tag4/#id")
String id;
}
Valid Use Case #2
import java.util.List;
import javax.xml.bind.annotation.*;
import org.eclipse.persistence.oxm.annotations.XmlPath;
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "name", propOrder = { "tag4", "id" })
public class newBean {
#XmlPath("tag4/#id")
List<String> id;
}
Invalid Use Case
import java.util.List;
import javax.xml.bind.annotation.*;
import org.eclipse.persistence.oxm.annotations.XmlPath;
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "name", propOrder = { "tag4", "id" })
public class newBean {
#XmlElement(required=true)
List<String> tag4;
#XmlPath("tag4/#id")
List<String> id;
}
Mapping Your Use Case
You could introduce an object that corresponds to the tag4 element that has two properties corresponding to the id attribute and text. This would work with any JAXB (JSR-222) implementation.
newBean
import java.util.List;
import javax.xml.bind.annotation.*;
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "name", propOrder = { "tag4", "id" })
public class newBean {
List<Tag4> tag4;
}
Tag4
import javax.xml.bind.annotation.*;
#XmlAccessorType(XmlAccessType.FIELD)
public class Tag4 {
#XmlAttribute
private String id;
#XmlValue
private String value;
}
For More Information
http://blog.bdoughan.com/2011/06/jaxb-and-complex-types-with-simple.html

JAXB - Unexpected elements in XML output

I have a class called Building.
It has a list of BuildingBenchAssociation records (List<BuildingBenchAssociation> benches)
BuildingBenchAssociation has a composite id made up of buildingId and benchId
The ID is represented by separate class called BuildingBenchAssociationPKwhich has only two properties - buildingId and benchId
This is the output I get when I marshal a Building instance
<building buildingId="9">
<benches>
DOMRecord(<?xml version="1.0" encoding="UTF-8"?><buildingBenchAssociation><benchId>245865</benchId><buildingId>9</buildingId></buildingBenchAssociation>)
</benches>
<benches>
DOMRecord(<?xml version="1.0" encoding="UTF-8"?><buildingBenchAssociation><benchId>245866</benchId><buildingId>9</buildingId></buildingBenchAssociation>)
</benches>
<benches>
But I don't want DOMRecord(<?xml version="1.0" encoding="UTF-8"?> to appear in the output. Required output is something like this:
<building buildingId="9">
<benches>
<buildingBenchAssociation><benchId>245865</benchId><buildingId>9</buildingId></buildingBenchAssociation>
</benches>
<benches>
<buildingBenchAssociation><benchId>245866</benchId><buildingId>9</buildingId></buildingBenchAssociation>
</benches>
<benches>
What's wrong and how do I correct it? I am using the Eclipselink MOXy library.
Classes for reference:
Class 1
#Entity
#Table(name="building")
#XmlRootElement
public class Building implements Serializable {
....
private List<BuildingBenchAssociation> benchs = new ArrayList<BuildingBenchAssociation>();
#XmlIDREF
#OneToMany(mappedBy="building")
public List<BuildingBenchAssociation> getBenchs() {
return benchs;
}
public void setBenchs(List<BuildingBenchAssociation> benchs) {
this.benchs = benchs;
}
}
Class 2
#Entity
#Table(name="building_bench_rel")
#XmlRootElement
public class BuildingBenchAssociation implements Serializable {
private static final long serialVersionUID = 1L;
private BuildingBenchAssociationPK idx;
private Bench bench;
private Building building;
private byte alertFlags;
private byte status;
public BuildingBenchAssociation() {
idx=new BuildingBenchAssociationPK();
}
#XmlID
#XmlPath(".")
#Id
public BuildingBenchAssociationPK getIdx() {
return this.idx;
}
public void setIdx(BuildingBenchAssociationPK id) {
this.idx = id;
}
#Column(name="ALERT_FLAGS")
public byte getAlertFlags() {
return this.alertFlags;
}
public void setAlertFlags(byte alertFlags) {
this.alertFlags = alertFlags;
}
#Column(name="STATUS", insertable=false, updatable=false)
public byte getStatus() {
return this.status;
}
public void setStatus(byte status) {
this.status = status;
}
#XmlIDREF
#ManyToOne
#JoinColumn(name="BENCH_ID",insertable=false,updatable=false)
public Bench getBench() {
return bench;
}
public void setBench(Bench bench) {
this.bench = bench;
this.idx.setBenchId(bench==null?null:bench.getBenchId());
}
#XmlIDREF
#ManyToOne
#JoinColumn(name="BUILDING_ID",insertable=false,updatable=false)
public Building getBuilding() {
return building;
}
public void setBuilding(Building building) {
this.building = building;
this.idx.setBuildingId(building==null?null:building.getBuildingId());
}
}
Class 3
#Embeddable
#XmlRootElement
public class BuildingBenchAssociationPK implements Serializable {
...
private Integer buildingId;
private Integer benchId;
public BuildingBenchAssociationPK() {
}
#XmlKey
#Column(name="BUILDING_ID")
public Integer getBuildingId() {
return this.buildingId;
}
public void setBuildingId(Integer buildingId) {
this.buildingId = buildingId;
}
#XmlKey
#Column(name="BENCH_ID")
public Integer getBenchId() {
return this.benchId;
}
public void setBenchId(Integer benchId) {
this.benchId = benchId;
}
}

Below is how you can currently map this use case using MOXy. I have opened the following enhancement request to make this use case easier to map:
http://bugs.eclipse.org/407460
REFERENCED OBJECT
Embedded ID (EmployeeId)
Below is an example of an embedded ID class:
import java.math.BigDecimal;
import javax.persistence.*;
import javax.xml.bind.annotation.*;
#Embeddable
#XmlAccessorType(XmlAccessType.FIELD)
public class EmployeeId {
#Column(name="E_ID")
BigDecimal eId;
String country;
}
Class with Embedded ID (Employee)
We want to use the embedded ID class for as the key in an XML relationship. Currently MOXy does not allow this to be done via annotations, so we will leverage the #XmlCustomizer annotation to programmatically modify the metadata.
import java.util.List;
import javax.persistence.*;
import javax.xml.bind.annotation.*;
import org.eclipse.persistence.oxm.annotations.*;
#Entity
#IdClass(EmployeeId.class)
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
#XmlCustomizer(EmployeeCustomizer.class)
public class Employee {
#EmbeddedId
#XmlPath(".")
EmployeeId id;
#OneToMany(mappedBy="contact")
List<PhoneNumber> contactNumber;
}
Customize Mapping Metadata for Employee (EmployeeCustomizer)
In the customizer class we will specify the XPaths for the mappings that compose the key on the embedded class.
import org.eclipse.persistence.config.DescriptorCustomizer;
import org.eclipse.persistence.descriptors.ClassDescriptor;
public class EmployeeCustomizer implements DescriptorCustomizer {
#Override
public void customize(ClassDescriptor descriptor) throws Exception {
descriptor.addPrimaryKeyFieldName("eId/text()");
descriptor.addPrimaryKeyFieldName("country/text()");
}
}
REFERRING OBJECT
PhoneNumber
We are also going to need to programatically add the mapping based on the composite key, so once again we will use the #XmlCustomizer annotation.
import javax.persistence.*;
import javax.xml.bind.annotation.*;
import org.eclipse.persistence.oxm.annotations.*;
#Entity
#XmlAccessorType(XmlAccessType.FIELD)
#XmlCustomizer(PhoneNumberCustomizer.class)
public class PhoneNumber {
#ManyToOne
#JoinColumns({
#JoinColumn(name="E_ID", referencedColumnName = "E_ID"),
#JoinColumn(name="E_COUNTRY", referencedColumnName = "COUNTRY")
})
Employee contact;
}
Customize Mapping Metadata for PhoneNumber (PhoneNumberCustomizer)
In this customizer we will remove the default mapping, and programatically create the new one based on the composite keys.
import org.eclipse.persistence.config.DescriptorCustomizer;
import org.eclipse.persistence.descriptors.ClassDescriptor;
import org.eclipse.persistence.oxm.mappings.XMLObjectReferenceMapping;
public class PhoneNumberCustomizer implements DescriptorCustomizer {
#Override
public void customize(ClassDescriptor descriptor) throws Exception {
descriptor.removeMappingForAttributeName("contact");
XMLObjectReferenceMapping contactMapping = new XMLObjectReferenceMapping();
contactMapping.setAttributeName("contact");
contactMapping.setReferenceClass(Employee.class);
contactMapping.addSourceToTargetKeyFieldAssociation("contact/#eID", "eId/text()");
contactMapping.addSourceToTargetKeyFieldAssociation("contact/#country", "country/text()");
descriptor.addMapping(contactMapping);
}
}
DEMO CODE
The following demo code can be used to demonstrate that everything works:
Demo
import java.io.File;
import javax.xml.bind.*;
public class Demo {
public static void main(String[] args) throws Exception {
JAXBContext jc = JAXBContext.newInstance(Employee.class);
Unmarshaller unmarshaller = jc.createUnmarshaller();
File xml = new File("input.xml");
Employee employee = (Employee) unmarshaller.unmarshal(xml);
Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
marshaller.marshal(employee, System.out);
}
}
input.xml/Output
<?xml version="1.0" encoding="UTF-8"?>
<employee>
<eId>10</eId>
<country>Canada</country>
<contactNumber>
<contact eID="10" country="Canada"/>
</contactNumber>
<contactNumber>
<contact eID="10" country="Canada"/>
</contactNumber>
</employee>
FOR MORE INFORMATION
http://wiki.eclipse.org/EclipseLink/Examples/MOXy/JPA/EmbeddedIdClass

Is it possible to #XmlElement annotate a method with non-stardard name?

This is what I'm doing:
#XmlType(name = "foo")
#XmlAccessorType(XmlAccessType.NONE)
public final class Foo {
#XmlElement(name = "title")
public String title() {
return "hello, world!";
}
}
JAXB complains:
com.sun.xml.bind.v2.runtime.IllegalAnnotationsException: 2 counts of IllegalAnnotationExceptions
JAXB annotation is placed on a method that is not a JAXB property
this problem is related to the following location:
at #javax.xml.bind.annotation.XmlElement(nillable=false, name=title, required=false, defaultValue=, type=class javax.xml.bind.annotation.XmlElement$DEFAULT, namespace=##default)
at com.example.Foo
What to do? I don't want (and can't) rename the method.

There are a couple of different options:
Option #1 - Introduce a Field
If the value is constant as it is in your example, then you could introduce a field into your domain class and have JAXB map to that:
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlType;
#XmlType(name = "foo")
#XmlAccessorType(XmlAccessType.NONE)
public final class Foo {
#XmlElement
private final String title = "hello, world!";
public String title() {
return title;
}
}
Option #2 - Introduce a Property
If the value is calculated then you will need to introduce a JavaBean accessor and have JAXB map to that:
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlType;
#XmlType(name = "foo")
#XmlAccessorType(XmlAccessType.NONE)
public final class Foo {
public String title() {
return "hello, world!";
}
#XmlElement
public String getTitle() {
return title();
}
}

There might be a better way, but the first solution that comes to mind is:
#XmlElement(name = "title")
private String title;
public String getTitle() {
return title();
}
Why is it you can't name your method according to Java conventions anyway?