我想用JaXB验证xml文档。代码:SchemaFactoryfactory=SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);Schemaschema=factory.newSchema(newStreamSource(newFile("D:/liferay-develop/workspace/cat_test/v2/STD_MP.xsd")));UnmarshallerjaxbUnmarshaller=jaxbContext.createUnmarshaller();jaxbUnmarshaller.setS