JAXB returns "null" string instead of null

Question

on setting an element:

element.setValue(null)

it marshalls the XML to

<element>
 <value>null<value>
</element>

I am expecting it to be:

<element>
  <value/>
</element>

or

 <element />

Answer 1

JAXB does not marshal a null value as:

<foo>null</foo>

By default it will not marshal the element. If you annotate it with @XmlElement(nillable=true) the xsi:nil attribute will be used.

For More Information

• http://blog.bdoughan.com/2012/04/binding-to-json-xml-handling-null.html

Answer 2

You need to put @XmlValue annotation on getter method value

@XmlValue
public String getValue(){
}

further see How to represent null value as empty element with JAXB?

Answer 3

Try to set to element.setValue("") , instead of null directly for the desired output.

Answer 4

You have two options:

1. set the value with an empty string and do that each time you want an empty field in the file

2. In the getter method of value you do so:

   public String getValue(){
    if(value == null)
          return null;
    return value;
   }
   

   In this case if you don't give a value to this field then you will have an empty element. Personnally, I prefer the first solution