Unmarshalling in JAXB - jaxb

Question

I have the following tester.xml file which contains some info about events.
<?xml version="1.0"?>
<resultset xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<row>
<field name="esid">539661</field>
<field name="esname">Title 01</field>
<field name="eslink">http://www.some_event_link.com</field>
<field name="estext">Event description 01</field>
<field name="esinfo" xsi:nil="true" />
<field name="espicture_small">http://www.some_event_link.com/media/small_image.jpg</field>
<field name="espicture">http://www.some_event_link.com/media/some_image..gif</field>
<field name="espicture_big">http://www.some_event_link.com/media/big_image.jpg</field>
<field name="esbegin">2000-11-22</field>
<field name="esend">2011-12-15</field>
<field name="eventid">1379305</field>
<field name="eventname">Event name 01</field>
<field name="eventdate">2011-10-12</field>
<field name="eventtime">19:00:00</field>
<field name="eventlink">http://www.mysite.com/tickets.html</field>
<field name="eventvenue">Event venue 01</field>
</row>
<row>
<field name="esid">539636</field>
<field name="esname">Title 02</field>
<field name="eslink">http://www.some_event_link.com</field>
<field name="estext">Event description 02</field>
<field name="esinfo" xsi:nil="true" />
<field name="espicture_small">http://www.some_event_link.com/media/small_image.jpg</field>
<field name="espicture">http://www.some_event_link.com/media/some_image..gif</field>
<field name="espicture_big">http://www.some_event_link.com/media/big_image.jpg</field>
<field name="esbegin">2000-10-10</field>
<field name="esend">2011-11-01</field>
<field name="eventid">1379081</field>
<field name="eventname">Event name 01</field>
<field name="eventdate">2011-10-12</field>
<field name="eventtime">14:00:00</field>
<field name="eventlink">http://www.mysite.com/tickets.html</field>
<field name="eventvenue">Event venue 02</field>
</row>
Also I have my XML mapping classes as follows.
First is the class corresponding to the tag < resultset >
package com.wapice.xml.beans;
import java.util.ArrayList;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
#XmlRootElement(name = "resultset")
public class Resultset {
private ArrayList<Row> rowsList;
#XmlElement(required = true, name = "row")
public ArrayList<Row> getRowsList() {
return rowsList;
}
public void setRowsList(ArrayList<Row> rowsList) {
this.rowsList = rowsList;
}
}
Next is the class which corresponds to the tag < row >
package com.wapice.xml.beans;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlType;
#XmlRootElement(name = "row")
#XmlType(propOrder = {"field"})
public class Row {
private String field;
#XmlElement(required = true, name = "field")
public String getField() {
return field;
}
public void setField(String field) {
this.field = field;
}
}
I tried to Unmarshall this xml into objects & print the field names & values on my console with the following code fragment.
try {
JAXBContext context = JAXBContext.newInstance(Resultset.class);
Unmarshaller unmarshaller = context.createUnmarshaller();
Resultset resultSet = (Resultset)unmarshaller.unmarshal(new FileReader("tester.xml"));
for(Row row : resultSet.getRowsList()){
System.out.println("Field : " +row.getField());
}
}
catch (JAXBException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
But when I run the above code, it only prints the last field's value. The output is as follows.
Field : Event venue 01
Field : Event venue 02
Can someone please tell me what I'm doing wrong here & it would be much appreciated if someone could tell me how to print all my < field > along with their names & values.
Thanks in advance.
Asela.

Answer 1

You could introduce a Field object:
package com.wapice.xml.beans;
import javax.xml.bind.annotation.*;
public class Field {
#XmlAttribute name;
#XmlValue value;
}
And have the Row object hold onto a List of them:
package com.wapice.xml.beans;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlType;
#XmlRootElement(name = "row")
#XmlType(propOrder = {"field"})
public class Row {
private List<Field> fields;
#XmlElement(required = true, name = "field")
public List<Field> getFields() {
return field;
}
public void setField(List<Field> fields) {
this.fields = fields;
}
}
For More Information
http://blog.bdoughan.com/2010/09/jaxb-collection-properties.html
http://blog.bdoughan.com/2011/06/jaxb-and-complex-types-with-simple.html

Answer 2

I managed to solve my issue with your post & it was really really helpful. Thank you so very much for that. However I had to do some modifications to get it working as my mapping classes were throwing the following exceptions.
com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException: 2 counts of IllegalAnnotationExceptions
Class has two properties of the same name "rowsList"
this problem is related to the following location:
at public java.util.ArrayList com.wapice.xml.beans.Resultset.getRowsList()
at com.wapice.xml.beans.Resultset
this problem is related to the following location:
at private java.util.ArrayList com.wapice.xml.beans.Resultset.rowsList
at com.wapice.xml.beans.Resultset
Class has two properties of the same name "fieldsList"
this problem is related to the following location:
at public java.util.ArrayList com.wapice.xml.beans.Row.getFieldsList()
at com.wapice.xml.beans.Row
at private java.util.ArrayList com.wapice.xml.beans.Resultset.rowsList
at com.wapice.xml.beans.Resultset
this problem is related to the following location:
at private java.util.ArrayList com.wapice.xml.beans.Row.fieldsList
at com.wapice.xml.beans.Row
at private java.util.ArrayList com.wapice.xml.beans.Resultset.rowsList
at com.wapice.xml.beans.Resultset
Then I changed the names of the related getters/setters & it worked fine.
Following is how I changed it.
----------------
Class Resultset
----------------
#XmlElement(required = true, name = "row")
private ArrayList<Row> rowsList; // I kept the same name for this attribute
public ArrayList<Row> getRowsList() { // I changed this to getRows()
return rowsList;
}
public void setRowsList(ArrayList<Row> rowsList) { // I changed this to setRows()
this.rowsList = rowsList;
}
----------
Class Row
----------
#XmlElement(required = true, name = "field")
private ArrayList<Field> fieldsList; // I kept the same name for this attribute
public void setFieldsList(ArrayList<Field> fieldsList) { // I changed this to getFields()
this.fieldsList = fieldsList;
}
public ArrayList<Field> getFieldsList() { // I changed this to setFields()
return fieldsList;
}
Hope this helps someone else too.