Why classes generated from xml are deprecated?

I have some classes which are generated from xml. For example :

@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "", propOrder = { "key", "name"})
@XmlRootElement(name = "caData")
public class CaData {

    @XmlElement(required = true)
    protected String key;

    @XmlElement(required = true)
    protected String name;
}

and when I try to use them somewhere

private CaData caData;

or pass them as a parameter

public construct(String name, CaData caData) {
    this.caData = caData;
    this.name = name;
}

I get the notifier:

The type CaData is deprecated.

Where am I wrong ?