Difference between revisions of "EclipseLink/Examples/MOXy/Spring/JAXBAnnotations"

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(Configuration: applicationContext.xml)
(Configuration: applicationContext.xml)
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* xmlHelper
 
* xmlHelper
 
** This is the class that will do all of the work, i.e. marshal and unmarshal
 
** This is the class that will do all of the work, i.e. marshal and unmarshal
** An instance of <code>org.springframework.oxm.jaxb.Jaxb2Marshaller</code> will be injected by Spring
+
** We use the "marshaller" property to indicate that we want Spring to inject an instance of <code>org.springframework.oxm.jaxb.Jaxb2Marshaller</code>
 
* jaxbMarshaller
 
* jaxbMarshaller
 
** This is an instance of the <code>org.springframework.oxm.jaxb.Jaxb2Marshaller</code> class that will be injected into our xmlHelper
 
** This is an instance of the <code>org.springframework.oxm.jaxb.Jaxb2Marshaller</code> class that will be injected into our xmlHelper

Revision as of 16:06, 27 July 2010

In order to use EclipseLink JAXB with the Spring Framework, you simply need a jaxb.properties file and an eclipselink.jar on the classpath. No other special configuration is required. This example will demonstrate how to configure Spring to use EclipseLink JAXB. The model classes make use of standard JAXB annotations as well as MOXy extensions.

The latest version of EclipseLink can be found on the EclipseLink download page.
The latest version of the Spring Framework can be found on the Spring download page.
The model used for this example can be found on the following pages:

Configuration: applicationContext.xml

The following XML file will be used to configure our beans:

<?xml version="1.0" encoding="UTF-8"?>
<beans 
    xmlns="http://www.springframework.org/schema/beans" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd">
    <bean id="jaxbMarshaller" class="org.springframework.oxm.jaxb.Jaxb2Marshaller">
        <property name="contextPath" value="example.gettingstarted"/>
    </bean>
    <bean id="xmlHelper" class="example.gettingstarted.XMLHelper">
        <property name="marshaller" ref="jaxbMarshaller"/>
    </bean>
</beans>

Two beans are being defined here:

  • xmlHelper
    • This is the class that will do all of the work, i.e. marshal and unmarshal
    • We use the "marshaller" property to indicate that we want Spring to inject an instance of org.springframework.oxm.jaxb.Jaxb2Marshaller
  • jaxbMarshaller
    • This is an instance of the org.springframework.oxm.jaxb.Jaxb2Marshaller class that will be injected into our xmlHelper
    • We use the "contextPath" property to indicate the location of the model classes, jaxb.properties, and an ObjectFactory class or jaxb.index file

Following is the jaxb.properties file that tells Spring to use EclipseLink JAXB:

javax.xml.bind.context.factory = org.eclipse.persistence.jaxb.JAXBContextFactory

Bootstrapping the Application

The standard Spring bean lookup method can be used to gain access to the xmlHelper bean:

// initialize IoC Container
ApplicationContext appContext = new ClassPathXmlApplicationContext("applicationContext.xml");
// retrieve the XMLHelper instance from the Container
XMLHelper xmlHelper = (XMLHelper) appContext.getBean("xmlHelper");

Java Source

Following is the XMLHelper class:

example.gettingstarted.XMLHelper.java

package example.gettingstarted;
 
import java.io.IOException;
 
import javax.xml.transform.Result;
import javax.xml.transform.Source;
 
import org.springframework.oxm.XmlMappingException;
import org.springframework.oxm.jaxb.Jaxb2Marshaller;
 
public class XMLHelper {
    private Jaxb2Marshaller marshaller;
 
    /**
     * Unmarshal a given source
     */
    public Object load(Source source) throws XmlMappingException, IOException {
        return marshaller.unmarshal(source);
    }
 
    /**
     * Marshal a given Object to a Result
     */
    public void save(Object obj, Result result) throws XmlMappingException, IOException {
        marshaller.marshal(obj, result);
    }
 
    /**
     * This method is used by Spring to inject an instance of Jaxb2Marshaller
     */
    public void setMarshaller(Jaxb2Marshaller marshaller) {
        this.marshaller = marshaller;
    }
}