Error while unmarshalling in java

Question

I have an xml file already containing,

**< ?xml version="1.0" encoding="UTF-8" standalone="yes"?>

< customer id="100">

< age>22< /age>

< name>naveen< /name> < /customer>**

for which my POJO class is

public class Customer {

String name;
int age;
int id;

public String getName() {
    return name;
}

public int getAge() {
    return age;
}

public int getId() {
    return id;
}

}

I am trying to unmarshall this by using JAXB as,

   File file = new File("sample.txt");
   JAXBContext jaxbContext = JAXBContext.newInstance(Customer.class);
   Unmarshaller jaxbUnmarshaller = jaxbContext.createUnmarshaller();
   Customer customer = (Customer) jaxbUnmarshaller.unmarshal(file);
   System.out.println(customer);

But I am getting an exception as

unexpected element (uri:"", local:"customer"). Expected elements are (none)

Please help me out.

Answer 1

Currently there isn't enough information in you class for JAXB to know which class to instantiate based on the root element. You can do one of the following:

1. Add @XmlRootElement on your Customer class to explicitly map the Customer class to the customer root element.

2. Use an unmarshal method that takes a Class parameter:

   JAXBElement<Customer> je = unmarshaller.unmarshal(source, Customer.class);
   Customer customer = je.getValue();
   

For More Information

• http://blog.bdoughan.com/2012/07/jaxb-no-annotations-required.html
• http://blog.bdoughan.com/2012/07/jaxb-and-root-elements.html

Answer 2

There might be 2 issue
1 - Correct the format of xml, I could saw spaces in the tag like use instead of < use> better to use below xml

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<customer id="100">
    <age>22</age>
    <name>naveen</name> 
</customer>

2 - and annotate your Jaxb class - use the below

@XmlRootElement
public class Customer {
@XmlElement
String name;
@XmlElement
int age;
@XmlAttribute
int id;

public String getName() {
    return name;
}

public int getAge() {
    return age;
}

public int getId() {
    return id;
}
}