Cast JAXB2 generated object to JAXBElement? - jaxb

Question

I have 2 sets of XSD's, one that generates RPC based calls, and another that defines the product specific methods. The RpcType object (generated by JAXB2) has a 'setRpcOperation' method defined by:
RpcType.setRpcOperation(JAXBElement<? extends RpcOperationType>)
That 'RpcOperation' object should be the 'specific product method' described above. One example is (also generated by JAXB2):
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "get-user-stats", propOrder = {
"reset"
})
public class GetUserStats {
protected Boolean reset;
/**
* Gets the value of the reset property.
*
* #return
* possible object is
* {#link Boolean }
*
*/
public Boolean isReset() {
return reset;
}
/**
* Sets the value of the reset property.
*
* #param value
* allowed object is
* {#link Boolean }
*
*/
public void setReset(Boolean value) {
this.reset = value;
}
}
Now, is it possible to create an instance of 'GetUserStatus' and add it to the RpcType object via setRpcOperation?

Answer 1

This type of scenario is common:
One schema to represent the message
Multiple schemas to represent the payload.
Below is one way this could be done:
Message Schema - message.xsd
Have one XML schema to represent your message envelope. Introduce one type to represent the body of the message. This type will be extended by the different payloads.
<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
targetNamespace="http://www.example.org/message"
xmlns="http://www.example.org/message"
elementFormDefault="qualified">
<xsd:element name="message">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="body" type="body"/>
</xsd:sequence>
</xsd:complexType>
</xsd:element>
<xsd:complexType name="body">
</xsd:complexType>
</xsd:schema>
Payload Schema - customer.xsd
This schema corresponds to a specific type of message payload. Notice how the customer type extends the body type from the message schema.
<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema
targetNamespace="http://www.example.org/customer"
xmlns="http://www.example.org/customer"
xmlns:m="http://www.example.org/message"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
elementFormDefault="qualified">
<xsd:import schemaLocation="message.xsd" namespace="http://www.example.org/message"/>
<xsd:complexType name="customer">
<xsd:complexContent>
<xsd:extension base="m:body">
<xsd:sequence>
<xsd:element name="name" type="xsd:string"/>
</xsd:sequence>
</xsd:extension>
</xsd:complexContent>
</xsd:complexType>
</xsd:schema>
org.example.message.package-info
This class was generated from message.xsd.
#javax.xml.bind.annotation.XmlSchema(namespace = "http://www.example.org/message", elementFormDefault = javax.xml.bind.annotation.XmlNsForm.QUALIFIED)
package org.example.message;
org.example.message.Message
This class was generated from message.xsd.
package org.example.message;
import javax.xml.bind.annotation.*;
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "", propOrder = {
"body"
})
#XmlRootElement(name = "message")
public class Message {
#XmlElement(required = true)
protected Body body;
public Body getBody() {
return body;
}
public void setBody(Body value) {
this.body = value;
}
}
org.example.message.Body
This class was generated from message.xsd.
package org.example.message;
import javax.xml.bind.annotation.*;
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "body")
public class Body {
}
org.example.customer.package-info
This class was generated from customer.xsd.
#javax.xml.bind.annotation.XmlSchema(namespace = "http://www.example.org/customer", elementFormDefault = javax.xml.bind.annotation.XmlNsForm.QUALIFIED)
package org.example.customer;
org.example.customer.Customer
This class was generated from customer.xsd.
package org.example.customer;
import javax.xml.bind.annotation.*;
import org.example.message.Body;
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType(name = "customer", propOrder = {
"name"
})
public class Customer extends Body {
#XmlElement(required = true)
protected String name;
public String getName() {
return name;
}
public void setName(String value) {
this.name = value;
}
}
Demo Class
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import org.example.customer.*;
import org.example.message.*;
public class Demo {
public static void main(String[] args) throws Exception {
JAXBContext jc = JAXBContext.newInstance(Message.class, Customer.class);
Message message = new Message();
Customer customer = new Customer();
customer.setName("Jane Doe");
message.setBody(customer);
Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
marshaller.marshal(message, System.out);
}
}
Output
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<message xmlns="http://www.example.org/message" xmlns:ns2="http://www.example.org/customer">
<body xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="ns2:customer">
<ns2:name>Jane Doe</ns2:name>
</body>
</message>
EDIT #1
In response to your second question (Cast JAXB2 generated object to JAXBElement?)
I don't see where the JAXBElement comes into play with this example. I am able to run the following code:
import generated.GetFailedLoginCount;
import ietf.params.xml.ns.netconf.base._1.RpcType;
public class Demo {
public static void main(String[] args) {
RpcType rpc = new RpcType();
rpc.setMessageId("123");
GetFailedLoginCount rpcOperation = new GetFailedLoginCount();
rpc.setRpcOperation(rpcOperation);
}
}
EDIT #2
After changing the import to import to http://www.iana.org/assignments/xml-registry/schema/netconf.xsd I'm seeing the same behaviour as you.
To set the property correctly you will need to do something like:
RpcType rpc = new RpcType();
GetFailedLoginCount rpcOperation = new GetFailedLoginCount();
rpcOperation.setReset(true);
JAXBElement<GetFailedLoginCount> rpcOperationJE = new JAXBElement(new QName("foo"), GetFailedLoginCount.class, rpcOperation);
rpc.setRpcOperation(rpcOperationJE);
JAXBElement supplies the element name for the GetFailedLoginCount value. This is required because the element corresponding to the rpcOperation property is substitutable:
<xs:element name="get-config" type="getConfigType" substitutionGroup="rpcOperation" />
In your schema that imports netconf.xsd you should have an element of type "get-failed-login-count" that can be substituted for "rpcOperation". This will be supplied as a QName to the JAXBElement. Since we used element name "foo" above the schema update would look like:
<xs:element name="foo" type="get-failed-login-count" substitutionGroup="rpcOperation" />

Answer 2

Ok, so here is a subset of what I am trying to do. The above example was extremely helpful, but I still am not able to create a JAXBElement:
Base envelope can be found: http://www.iana.org/assignments/xml-registry/schema/netconf.xsd
Payload for rpcOperationType (I added the ** lines):
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:dmi="http://xml.juniper.net/dmi"
** xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0"
>
**<xs:import schemaLocation="netconf.xsd" namespace="urn:ietf:params:xml:ns:netconf:base:1.0"/>
<!-- get-failed-login-count -->
<xs:complexType name="get-failed-login-count">
**<xs:complexContent>
** <xs:extension base="netconf:rpcOperationType">
<xs:annotation>
<xs:appinfo>
<dmi:rpc-info>
<name>Get failed login count for Authentication failure and Exceeded user</name>
<description>
This command returns the Number of Logins refused due to exceeding allowed limits and Auth failure (24 hour moving window)
</description>
<rpc-reply-tag>failed-login-count</rpc-reply-tag>
</dmi:rpc-info>
</xs:appinfo>
</xs:annotation>
<xs:sequence>
<xs:element name="reset" type="xs:boolean" minOccurs="0">
<xs:annotation>
<xs:appinfo>
<dmi:param-info>
<name>Reset Stats</name>
<description>
This will govern the reseting of this statistics data. By default, the data is not reset.
</description>
</dmi:param-info>
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
** </xs:extension>
**</xs:complexContent>
</xs:complexType>
Now, the generated GetFailedLogin class extends RpcOperationType, but I am not sure how to set it in the RpcType object:
RpcType rpc = new RpcType();
rpc.setMessageId("123");
GetFailedLoginCount rpcOperation = new GetFailedLoginCount();
rpc.setRpcOperation(); // Expects JAXBElement<? Extends RpcOperationType>