@XStreamAsAttribute currently works dont works with enum types, its necessary a specialized converter, the annotation needs the same behavior for enums and object attributes.

Example,

public class Field {
@XStreamAsAttribute
String name;
        @XStreamAsAttribute
int bits;
@XStreamAsAttribute
Type type;

// set ang get
}

public enum Type {
TEXT ,
NUMBER;
}

public class TestEnumAttribute {
public static void main(String[] args) {
XStream xstream = new XStream(new DomDriver());
Field field = new Field();
field.setName("serial");
field.setBits(224);
field.setType(Type.TEXT);
Annotations.configureAliases(xstream, Field.class);
String xml = xstream.toXML(field);
System.out.println(xml);
}
}

Current result:
<fieldname="serial" bits="224">
  <type>TEXT</type>
<field>


The new return:
<field name="serial" bits="224" type="TEXT" />