XmlElementsJoinNodes is used in conjunction with XmlElements in order to specify the key references for the targets of the XmlElements annotation. There must be one XmlJoinNodes for each XmlElement This is similar to using XmlIDREF with XmlElements but allows customisation of the xpath for the source keys and allows for composite key relationships.

Example:

@XmlRootElement
public class Client {

  ...

  @XmlElements({
      @XmlElement(name="mail", type=Address.class),
      @XmlElement(name="phone", type=PhoneNumber.class)
  })
  @XmlElementsJoinNodes({
      @XmlJoinNodes({
          @XmlJoinNode(xmlPath="mail/@id", referencedXmlPath="@aid"),
          @XmlJoinNode(xmlPath="mail/type/text()", referencedXmlPath="@type")
      }),
      @XmlJoinNodes({
          @XmlJoinNode(xmlPath="phone/@id", referencedXmlPath="@pid"),
          @XmlJoinNode(xmlPath="phone/type/text()", referencedXmlPath="@type")
      })
  })
  public Object preferredContactMethod;