javax.xml.bind.JAXBContext Java Examples

/**
 * Map a Token instance to its XML representation.
 *
 * @return a String with the description of this object in XML.
 */
public String toXML() {
    StringWriter sw = new StringWriter();
    String xml = "";

    try {
        JAXBContext context = JAXBContext.newInstance(this.getClass());
        Marshaller marshaller = context.createMarshaller();

        marshaller.marshal(this, sw);
        xml = sw.toString();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return xml;
}
 

public static String marshallToString(Object object, String thePackage) {
	String rawObject = null;

	try {
		JAXBContext jc = getContext(thePackage);
		Marshaller marshaller = jc.createMarshaller();
		marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.FALSE);
		marshaller.setProperty(Marshaller.JAXB_FRAGMENT, Boolean.TRUE);
		marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		marshaller.marshal(object, baos);
		rawObject = baos.toString();
	} catch (JAXBException e) {
		logger.error(e.getMessage(),e);
	}
	
	return rawObject;
}
 

public void assertXmlMarshaling(Object typeTypeRelation, String expectedXml)
        throws Exception
    {
        JAXBContext jc = JAXBContext.newInstance(TypeTypeRelation.class);

        Marshaller marshaller = jc.createMarshaller();
        StringWriter stringWriter = new StringWriter();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
        // marshaller.setProperty("com.sun.xml.internal.bind.namespacePrefixMapper", new CustomNamespacePrefixMapper());
        marshaller.marshal(typeTypeRelation, stringWriter);
        String xml = stringWriter.toString();

//        System.out.println(xml); // run test, paste xml output into XML, comment out this line.

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        Object actual = unmarshaller.unmarshal(new StringReader(xml));
        Object expected = unmarshaller.unmarshal(new StringReader(expectedXml));
        Assert.assertEquals(expected, actual);
    }
 

@Override
public String toXML(T obj) {

    try {
        JAXBContext context = JAXBContext.newInstance(type);

        Marshaller m = context.createMarshaller();
        if(schemaLocation != null) {
            SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);

            StreamSource source = new StreamSource(getClass().getResourceAsStream(schemaLocation));
            Schema schema = schemaFactory.newSchema(source);
            m.setSchema(schema);
        }

        StringWriter writer = new StringWriter();

        m.marshal(obj, writer);
        String xml = writer.toString();

        return xml;
    } catch (Exception e) {
        System.out.println("ERROR: "+e.toString());
        return null;
    }
}
 

@SuppressWarnings("unchecked")
public static <V> List<V> parseListElement(Element parent,
                                       QName name,
                                       Class<?> c,
                                       JAXBContext context) throws JAXBException {
    List<V> list = new ArrayList<>();
    Node data = null;

    Unmarshaller u = context.createUnmarshaller();
    Node node = parent.getFirstChild();
    while (node != null) {
        if (node.getNodeType() == Node.ELEMENT_NODE && name.getLocalPart().equals(node.getLocalName())
            && name.getNamespaceURI().equals(node.getNamespaceURI())) {
            data = node;
            Object obj = unmarshal(u, data, c);
            if (obj != null) {
                list.add((V) obj);
            }
        }
        node = node.getNextSibling();
    }
    return list;
}
 

/**
 * The JAXB API will invoke this method via reflection
 */
public static JAXBContext createContext( String contextPath,
                                         ClassLoader classLoader, Map properties ) throws JAXBException {

    List<Class> classes = new ArrayList<Class>();
    StringTokenizer tokens = new StringTokenizer(contextPath,":");

    // each package should be pointing to a JAXB RI generated
    // content interface package.
    //
    // translate them into a list of private ObjectFactories.
    try {
        while(tokens.hasMoreTokens()) {
            String pkg = tokens.nextToken();
            classes.add(classLoader.loadClass(pkg+IMPL_DOT_OBJECT_FACTORY));
        }
    } catch (ClassNotFoundException e) {
        throw new JAXBException(e);
    }

    // delegate to the JAXB provider in the system
    return JAXBContext.newInstance(classes.toArray(new Class[classes.size()]),properties);
}
 

/**
 * @param <T> the type we want to convert the XML into
 * @param c the class of the parameterized type
 * @param xml the instance XML description
 * @return a deserialization of the XML into an object of type T of class class <T>
 * @throws JAXBException
 */
public static <T> T marshal(Class<T> c, String xml) throws JAXBException
{
    T res;

    if (c == xml.getClass())
    {
        res = (T) xml;
    }
    else
    {
        JAXBContext ctx = JAXBContext.newInstance(c);
        Unmarshaller marshaller = ctx.createUnmarshaller();
        res = (T) marshaller.unmarshal(new StringReader(xml));
    }

    return res;
}
 

/**
 * Deserializes binary data representing a xml-fragment to an object of
 * given class.
 *
 * @param data the binary data, representing a xml-fragment
 * @param clazz the class of the resulting object
 *
 * @return the deserialized object
 */
@SuppressWarnings( "unchecked" )
@Override
public <T> T deserialize( byte[] data, Class<T> clazz )
{
    try
    {

        JAXBContext context = JAXBContext.newInstance( clazz );
        Unmarshaller m = context.createUnmarshaller();
        Object o = m.unmarshal( new ByteArrayInputStream( data ) );
        return ( T ) o;
    }
    catch ( JAXBException e )
    {
        LOG.warn( e.getMessage() );
    }

    return null;
}
 

@SuppressWarnings("unchecked")
public JAXBContext getJAXBContext(Class<?> type, Type genericType) throws JAXBException {
    if (mc != null) {
        ContextResolver<JAXBContext> resolver =
            mc.getResolver(ContextResolver.class, JAXBContext.class);
        if (resolver != null) {
            JAXBContext customContext = resolver.getContext(type);
            if (customContext != null) {
                return customContext;
            }
        }
    }

    JAXBContext context = classContexts.get(type);
    if (context != null) {
        return context;
    }

    context = getPackageContext(type, genericType);

    return context != null ? context : getClassContext(type, genericType);
}
 

/**
 * @throws Exception
 */
public void testPersistenceVersion1() throws Exception {
    final JAXBContext ctx = JAXBContextFactory.newInstance(Persistence.class);
    final Unmarshaller unmarshaller = ctx.createUnmarshaller();

    final URL resource = this.getClass().getClassLoader().getResource("persistence-example.xml");
    final InputStream in = resource.openStream();
    final java.lang.String expected = readContent(in);

    final Persistence element = (Persistence) unmarshaller.unmarshal(new ByteArrayInputStream(expected.getBytes()));
    unmarshaller.setEventHandler(new TestValidationEventHandler());
    System.out.println("unmarshalled");

    final Marshaller marshaller = ctx.createMarshaller();
    marshaller.setProperty("jaxb.formatted.output", true);

    final ByteArrayOutputStream baos = new ByteArrayOutputStream();
    marshaller.marshal(element, baos);

    final String actual = new String(baos.toByteArray());

    final Diff myDiff = new Diff(expected, actual);
    myDiff.overrideElementQualifier(new ElementNameAndAttributeQualifier());
    assertTrue("Files are similar " + myDiff, myDiff.similar());
}
 

void initJaxbContext(final Method method) {
    Stream
            .concat(of(method.getGenericReturnType()),
                    of(method.getParameters())
                            .filter(p -> of(Path.class, Query.class, Header.class, QueryParams.class, Headers.class,
                                    HttpMethod.class, Url.class).noneMatch(p::isAnnotationPresent))
                            .map(Parameter::getParameterizedType))
            .map(RequestParser::toClassType)
            .filter(Objects::nonNull)
            .filter(cType -> cType.isAnnotationPresent(XmlRootElement.class)
                    || cType.isAnnotationPresent(XmlType.class))
            .forEach(rootElemType -> jaxbContexts.computeIfAbsent(rootElemType, k -> {
                try {
                    return JAXBContext.newInstance(k);
                } catch (final JAXBException e) {
                    throw new IllegalStateException(e);
                }
            }));
}
 

public boolean ReloadCustomFuels()
{
    boolean tResult = false;

    _mLogger.debug("CustomFuelsHandler will now try to load it's configuration");
    try
    {
        JAXBContext tJaxbCtx = JAXBContext.newInstance(CustomFuels.class);
        File tConfigFile = new File(_mConfigFileName);
        Unmarshaller jaxUnmarsh = tJaxbCtx.createUnmarshaller();
        CustomFuels tNewItemCollection = (CustomFuels) jaxUnmarsh.unmarshal(tConfigFile);
        _mLogger.debug("Config file has been loaded. Entering Verify state");

        _mCustomFuels = tNewItemCollection;
        tResult = true;

    }
    catch (Exception e)
    {
        e.printStackTrace();
    }

    return tResult;
}
 

@org.junit.Test
public void verifyConfigFederation() throws JAXBException {

    final JAXBContext jaxbContext = JAXBContext
            .newInstance(FedizConfig.class);

    FedizConfigurator configurator = new FedizConfigurator();
    FedizConfig configOut = createConfiguration(true);
    StringWriter writer = new StringWriter();
    jaxbContext.createMarshaller().marshal(configOut, writer);
    StringReader reader = new StringReader(writer.toString());
    configurator.loadConfig(reader);

    ContextConfig config = configurator.getContextConfig(CONFIG_NAME);
    Assert.assertNotNull(config);
    AudienceUris audience = config.getAudienceUris();
    Assert.assertEquals(3, audience.getAudienceItem().size());
    Assert.assertTrue(config.getProtocol() instanceof FederationProtocolType);
    FederationProtocolType fp = (FederationProtocolType) config
            .getProtocol();

    Assert.assertEquals(HOME_REALM_CLASS, fp.getHomeRealm().getValue());

}
 

private static WebApp parseXmlFragment() {
    InputStream precompiledJspWebXml = RegisterPrecompiledJSPInitializer.class.getResourceAsStream("/precompiled-jsp-web.xml");
    InputStream webXmlIS = new SequenceInputStream(
            new SequenceInputStream(
                    IOUtils.toInputStream("<web-app>", Charset.defaultCharset()),
                    precompiledJspWebXml),
            IOUtils.toInputStream("</web-app>", Charset.defaultCharset()));

    try {
        JAXBContext jaxbContext = new JAXBDataBinding(WebApp.class).getContext();
        Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
        WebApp webapp = (WebApp) unmarshaller.unmarshal(webXmlIS);
        try {
            webXmlIS.close();
        } catch (java.io.IOException ignored) {}
        return webapp;
    } catch (JAXBException e) {
        throw new RuntimeException("Could not parse precompiled-jsp-web.xml", e);
    }
}
 

@org.junit.Test
public void testClaimProcessor() throws JAXBException, IOException {
    final JAXBContext jaxbContext = JAXBContext.newInstance(FedizConfig.class);
    FedizConfigurator configurator = new FedizConfigurator();
    FedizConfig configOut = createConfiguration(true);
    StringWriter writer = new StringWriter();
    jaxbContext.createMarshaller().marshal(configOut, writer);
    StringReader reader = new StringReader(writer.toString());
    configurator.loadConfig(reader);
    
    FedizContext fedContext = configurator.getFedizContext(CONFIG_NAME);
    List<ClaimsProcessor> claimsProcessor = fedContext.getClaimsProcessor();
    Assert.assertNotNull(claimsProcessor);
    Assert.assertEquals(1, claimsProcessor.size());
    
    List<org.apache.cxf.fediz.core.Claim> inputClaims = new ArrayList<>();
    org.apache.cxf.fediz.core.Claim claim = new org.apache.cxf.fediz.core.Claim();
    claim.setClaimType(URI.create(CLAIM_TYPE_1));
    claim.setValue("Alice");
    inputClaims.add(claim);
    List<org.apache.cxf.fediz.core.Claim> processedClaims = claimsProcessor.get(0).processClaims(inputClaims);
    Assert.assertEquals(inputClaims, processedClaims);
}
 

public void reinit(IServiceSettings serviceSettings) {
	TCPIPProxySettings newSettings;
	if (serviceSettings instanceof TCPIPProxySettings) {
		newSettings = (TCPIPProxySettings) serviceSettings;
	} else {
		throw new ServiceException("Incorrect class of settings has been passed to init " + serviceSettings.getClass());
	}

       if(newSettings.isChangeTags() && (newSettings.getRulesAlias() != null)) {
		try {
			JAXBContext jc = JAXBContext.newInstance(new Class[]{Rules.class});
			Unmarshaller u = jc.createUnmarshaller();
			InputStream rulesAliasIS = dataManager.getDataInputStream(newSettings.getRulesAlias());
			JAXBElement<Rules> root = u.unmarshal(new StreamSource(rulesAliasIS),Rules.class);
			this.rules = root.getValue();
		} catch (Exception e) {
			disconnect();
			dispose();
			changeStatus(ServiceStatus.ERROR, "Error while reiniting", e);
			throw new EPSCommonException(e);
		}
	}
}
 

protected static JAXBContext getJaxbContext(Class clazz) {
		if (clazz == null){
			throw new RuntimeException("'clazz' must not be null");
		}
		JAXBContext jaxbContext = jaxbContexts.get(clazz);
		if (jaxbContext == null) {
			try {
				jaxbContext = JAXBContext.newInstance(clazz, CollectionWrapper.class);
				jaxbContexts.putIfAbsent(clazz, jaxbContext);
			} catch (JAXBException ex) {
//				throw new HttpMessageConversionException("Could not instantiate JAXBContext for class [" + clazz
//						+ "]: " + ex.getMessage(), ex);
				throw new RuntimeException("Could not instantiate JAXBContext for class [" + clazz
						+ "]: " + ex.getMessage(), ex);
			}
		}
		return jaxbContext;
	}
 

@Before
public void setUp() throws Exception {

   try {
      JAXBContext cntxt = JAXBContext.newInstance(JAXB_CONTEXT);
      InputStream in = this.getClass().getClassLoader().getResourceAsStream(XML_FILE);
      Unmarshaller um = cntxt.createUnmarshaller();
      JAXBElement<?> jel = (JAXBElement<?>) um.unmarshal(in);
      assertNotNull(jel.getValue());
      assertTrue(jel.getValue() instanceof PortletAppType);
      portletApp = (PortletAppType) jel.getValue();
   } catch (Exception e) {
      System.out.println("\nException during setup: " + e.getMessage()
            + "\n");
      throw e;
   }
}
 

/**
 * Return a {@link JAXBContext} for the given class.
 * @param clazz the class to return the context for
 * @return the {@code JAXBContext}
 * @throws HttpMessageConversionException in case of JAXB errors
 */
protected final JAXBContext getJaxbContext(Class<?> clazz) {
	Assert.notNull(clazz, "Class must not be null");
	JAXBContext jaxbContext = this.jaxbContexts.get(clazz);
	if (jaxbContext == null) {
		try {
			jaxbContext = JAXBContext.newInstance(clazz);
			this.jaxbContexts.putIfAbsent(clazz, jaxbContext);
		}
		catch (JAXBException ex) {
			throw new HttpMessageConversionException(
					"Could not instantiate JAXBContext for class [" + clazz + "]: " + ex.getMessage(), ex);
		}
	}
	return jaxbContext;
}
 

/**
 * <p>writeMigration.</p>
 *
 * @param dbMigration a {@link io.ebeaninternal.dbmigration.migration.Migration} object.
 * @param version     a {@link java.lang.String} object.
 * @return a boolean.
 */
protected boolean writeMigration(Migration dbMigration, String version) {
    if (migrationModel.isMigrationTableExist()) {
        scriptInfo = server.find(ScriptInfo.class, version);
        if (scriptInfo != null) {
            return false;
        }
    }
    scriptInfo = new ScriptInfo();
    scriptInfo.setRevision(version);
    try (StringWriter writer = new StringWriter()) {
        JAXBContext jaxbContext = JAXBContext.newInstance(Migration.class);
        Marshaller marshaller = jaxbContext.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
        marshaller.marshal(dbMigration, writer);
        writer.flush();
        scriptInfo.setModelDiff(writer.toString());
    } catch (JAXBException | IOException e) {
        throw new RuntimeException(e);
    }
    return true;
}
 

@Test
public void testSOAPPBindingNullMessage() throws Exception {
    d.setMessageObserver(new MessageReplayObserver("/org/apache/cxf/jaxws/sayHiResponse.xml"));

    URL wsdl = getClass().getResource("/wsdl/hello_world.wsdl");
    assertNotNull(wsdl);

    SOAPService service = new SOAPService(wsdl, SERVICE_NAME);
    assertNotNull(service);

    JAXBContext jc = JAXBContext.newInstance("org.apache.hello_world_soap_http.types");
    Dispatch<Object> disp = service.createDispatch(PORT_NAME, jc, Service.Mode.PAYLOAD);
    try {
        // Send a null message
        disp.invoke(null);
    } catch (SOAPFaultException e) {
        //Passed
        return;
    }

    fail("SOAPFaultException was not thrown");
}
 

public void printInterchangeStudentProgram(PrintStream ps) throws JAXBException {
    JAXBContext context = JAXBContext.newInstance(InterchangeStudentProgram.class);
    Marshaller marshaller = context.createMarshaller();
    marshaller.setProperty("jaxb.formatted.output", Boolean.TRUE);

    InterchangeStudentProgram interchangeStudentProgram = new InterchangeStudentProgram();

    List<Object> list = interchangeStudentProgram
            .getStudentProgramAssociationOrStudentSpecialEdProgramAssociationOrRestraintEvent();

    // StudentProgramAssociation
    // StudentSpecialEdProgramAssociation
    // RestraintEvent
    // StudentCTEProgramAssociation
    // StudentTitleIPartAProgramAssociation
    // ServiceDescriptor

    marshaller.marshal(interchangeStudentProgram, ps);
}
 

void init() {
    try {
        JAXBContext context = JAXBContext.newInstance("org.zstack.core.errorcode.schema");
        List<String> paths = PathUtil.scanFolderOnClassPath("errorCodes");
        for (String p : paths) {
            if (!p.endsWith(".xml")) {
                logger.warn(String.format("ignore %s which is not ending with .xml", p));
                continue;
            }

            File cfg = new File(p);
            Unmarshaller unmarshaller = context.createUnmarshaller();
            org.zstack.core.errorcode.schema.Error error =
                    (org.zstack.core.errorcode.schema.Error) unmarshaller.unmarshal(cfg);
            createErrorCode(error, p);
        }
    } catch (Exception e) {
        throw new CloudRuntimeException(e);
    }
}
 

/**
 * Marshal an object to a file, using provided JAXB context.
 *
 * @param object      instance to marshal
 * @param path        target file
 * @param jaxbContext proper context
 * @throws IOException        on IO error
 * @throws JAXBException      on JAXB error
 * @throws XMLStreamException on XML error
 */
public static void marshal (Object object,
                            Path path,
                            JAXBContext jaxbContext)
        throws IOException,
               JAXBException,
               XMLStreamException
{

    try (OutputStream os = Files.newOutputStream(path, CREATE);) {
        Marshaller m = jaxbContext.createMarshaller();
        XMLStreamWriter writer = new IndentingXMLStreamWriter(
                XMLOutputFactory.newInstance().createXMLStreamWriter(os, "UTF-8"));
        m.marshal(object, writer);
        os.flush();
    }
}
 

private Unmarshaller getUnmarshaller() throws JAXBException {
    JAXBContext jctx = JAXBContext.newInstance(WorkflowDefinition.class);
    Unmarshaller unmarshaller = jctx.createUnmarshaller();
    SchemaFactory sf = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
    URL schemaUrl = WorkflowDefinition.class.getResource("workflow.xsd");
    Schema schema = null;
    try {
        schema = sf.newSchema(new StreamSource(schemaUrl.toExternalForm()));
    } catch (SAXException ex) {
        throw new JAXBException("Missing schema workflow.xsd!", ex);
    }
    unmarshaller.setSchema(schema);
    ValidationEventCollector errors = new ValidationEventCollector() {

        @Override
        public boolean handleEvent(ValidationEvent event) {
            super.handleEvent(event);
            return true;
        }

    };
    unmarshaller.setEventHandler(errors);
    return unmarshaller;
}
 

/**
 * Marshals the given QueryResults object to its XML representations and
 * returns it as a String.
 * 
 * @param results
 *            The QueryResults object to marshal into XML.
 * @param out
 *            The OutputStream to which the XML representation will be
 *            written to.
 * @throws IOException
 *             If an error marshaling the QueryResults object occurred.
 */
public static String queryResultsToXml(final QueryResults results) throws IOException {
    // serialize the response
    try {
        StringWriter writer = new StringWriter();
        JAXBElement<QueryResults> item = factory.createQueryResults(results);
        JAXBContext context = JAXBContext.newInstance(QueryResults.class);
        Marshaller marshaller = context.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
        marshaller.setProperty(Marshaller.JAXB_FRAGMENT, Boolean.TRUE);
        marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");
        marshaller.marshal(item, writer);
        return writer.toString();
    } catch (JAXBException e) {
        IOException ioe = new IOException(e.getMessage());
        ioe.setStackTrace(e.getStackTrace());
        throw ioe;
    }
}
 

public ApiMessageProcessorImpl(Map<String, Object> config) {
    this.unitTestOn = CoreGlobalProperty.UNIT_TEST_ON;
    this.configFolders = (List <String>)config.get("serviceConfigFolders");

    populateGlobalInterceptors();

    try {
        JAXBContext context = JAXBContext.newInstance("org.zstack.portal.apimediator.schema");
        List<String> paths = new ArrayList<String>();
        for (String configFolder : this.configFolders) {
            paths.addAll(PathUtil.scanFolderOnClassPath(configFolder));
        }

        for (String p : paths) {
            if (!p.endsWith(".xml")) {
                logger.warn(String.format("ignore %s which is not ending with .xml", p));
                continue;
            }

            File cfg = new File(p);
            Unmarshaller unmarshaller = context.createUnmarshaller();
            Service schema = (Service) unmarshaller.unmarshal(cfg);
            createDescriptor(schema, cfg.getAbsolutePath());
        }

        if (!this.unitTestOn) {
            dump();
        }
    } catch (JAXBException e) {
        throw new CloudRuntimeException(e);
    }
}
 

private static JAXBContext getJaxbContext ()
        throws JAXBException
{
    // Lazy creation
    if (jaxbContext == null) {
        jaxbContext = JAXBContext.newInstance(TribeList.class);
    }

    return jaxbContext;
}
 

public static <T> Object unmarshal(final Class<T> type, final InputStream in, final boolean logErrors) throws ParserConfigurationException, SAXException, JAXBException {
    final InputSource inputSource = new InputSource(in);

    final SAXParserFactory factory = SAXParserFactory.newInstance();
    factory.setNamespaceAware(true);
    factory.setValidating(false);
    final SAXParser parser = factory.newSAXParser();

    final JAXBContext ctx = getContext(type);
    final Unmarshaller unmarshaller = ctx.createUnmarshaller();
    unmarshaller.setEventHandler(new ValidationEventHandler() {
        public boolean handleEvent(final ValidationEvent validationEvent) {
            if (logErrors) {
                System.out.println(validationEvent);
            }
            return false;
        }
    });

    unmarshaller.setListener(new Unmarshaller.Listener() {
        public void afterUnmarshal(final Object object, final Object object1) {
            super.afterUnmarshal(object, object1);
        }

        public void beforeUnmarshal(final Object target, final Object parent) {
            super.beforeUnmarshal(target, parent);
        }
    });


    final NamespaceFilter xmlFilter = new NamespaceFilter(parser.getXMLReader());
    xmlFilter.setContentHandler(unmarshaller.getUnmarshallerHandler());

    final SAXSource source = new SAXSource(xmlFilter, inputSource);

    return unmarshaller.unmarshal(source, type);
}
 

private Node createNode(JAXBElement jaxb, JAXBContext jc, String expression) throws  Exception{
    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
    DocumentBuilder db = dbf.newDocumentBuilder();
    Document document = db.newDocument();
    Marshaller marshaller = jc.createMarshaller();
    marshaller.marshal(jaxb, document);
    XPath xpath = XPathFactory.newInstance().newXPath();
    Node node = (Node) xpath.compile(expression).evaluate(document, XPathConstants.NODE);
    return node;
}