jaxb unmarshal Expected elements are (none)

Classes with XmlRootElement can be unmarshalled from XML elements simply by invoking the unmarshal method that takes one parameter. This is the simplest mode of unmarshalling. Unmarshalling with @XmlRootElement @XmlRootElement class Foo {   @XmlAttribute   String name;   @XmlElement   String content; } Unmarshaller u = …; Foo foo = (Foo)u.unmarshal(new File(“foo.xml”)); foo.xml <foo name=”something”>   <content>abc</content> </foo> However, sometimes you may need to unmarshal an instance of a type that does not…