JAXB Constructor with parameter which does not appears to be in xml

Good day, everyone. I was searching answer to my question in web, but I failed.. I have workaround, but just wondering, is it possible to do something like this: I have an *.xml:

<fileconfiguration>
    <attr name="example1" type="sql"  value="select value from A where id=?" priority="1"/>
    <attr name="example2" type="text" value="val2" priority="2"/>
</fileconfiguration>

I want to unmarshall that xml, but instead of having sql query in a “value” field of the object, I what to evaluate the value with parameter which is known before unmarshalling and it is unique for all objects in that xml.

@XmlRootElement(name = "fileconfiguration")
@XmlAccessorType(XmlAccessType.FIELD)
public class UNIFileConfiguration {

    @XmlElement(name = "attr", type = Attr.class)
    public Set<Attr> attrs = new TreeSet<Attr>();

    public FileConfiguration() {
    }

    public FileConfiguration(Set<Attr> attrs) {
        this.attrs = attrs;
    }

    public void setAttrs(Set<Attr> attrs) {
        this.attrs = attrs;
    }

    public Set getAttrs() {
        return this.etlAttributes;
    }
}

And the POJO class for Attr section:

@XmlRootElement(name = "attr")
public class Attr implements Comparable<Attr>{
    private String name;
    private String type;
    private String value;
    private int priority;
    private static BigInteger id;
    public Attr() {}
    public Attr(BigInteger id){this.id=id;}

    public String getName() { return name;}

    @XmlAttribute
    public void setName(String name) {this.name = name;}

    public String getType() {return type;}

    @XmlAttribute
    public void setType(String type) {this.type = type; }

    public String getValue() { return value;}

    @XmlAttribute
    public void setValue(String value) { 
       String str = StringUtils.EMPTY;
       if("text".equals(this.type)){str=value}
       if("sql".equals(this.type)){str=evaluateSQL(value, this.parameter)}
       this.value=str;
    }
    public int getPriority() {return priority;}

    @XmlAttribute
    public void setPriority(int priority) {this.priority = priority;}

    public String toString() {return "name: " + this.name;}

    public int compareTo(Attr o) {return this.priority - o.getPriority();}
}

is it possible to pass an external parameter so JAXB knows it at unmarshalling step?