How to maintain entry order information with JAXB? - jaxb

Question

Let's say I have an XML file like the following
<root>
<record>foo</record>
<record>bar</record>
</root>
I use JAXB to read in the record. Does JAXB keep the information of say bar comes before foo?
My gut feeling is NO, JAXB does not maintain this information. But then I am stuck since I actually need to get this information... Any recommendation... BTW, I can't change the format of the xml.
Thanks.

Answer 1

Have you actually tried it?
JAXB's #XmlType annotation as a propOrder property which defines the order of properties.
So you can do:
#XmlRootElemen(name="root")
#XmlType(propOrder={"record2", "record1"})
public class Root {
public String record1;
public String record2;
}
Update
The OP has edited his original XML from this:
<root>
<record2>
<record1>
</root>
To this:
<root>
<record>foo</record>
<record>bar</record>
</root>
My answer applies to the original XML with two elements record2 and record1.

Answer 2

Order & Repeated Elements
If your XML is like the following:
<root>
<record>foo</record>
<record>bar</record>
</root>
If you map a repeating element to a java.util.List the order of the elements will be maintained in the List.
#XmlElement(name="record")
public List<String> getRecords() {
return records;
}
Order & Non-Repeated Elements
If on the other hand your XML is like the following:
<root>
<hello>foo</hello>
<world>bar</world>
</root>
Using Marshaller
Then using Marshaller the order in which the elements are marshalled to XML will be controlled by:
The propOrder property on the #XmlType annotation.
The #XmlAccessorOrder annotation
Using Binder
Using Binder you parse your XML into a DOM and use Binder to unmarshal that. Then you can make changes to your object and apply those changes back to the DOM. This allows you to preserve aspects such as ordering from the orginal XML
Does JAXB support modification of existing XML documents without marshalling/unmarshalling?