Java JAXB-marshaller&；拆封工

我使用JAXB封送器将对象封送到System.out，如下所示：

JAXBContext ctxt = JAXBContext.newInstance(CONTEXT);
Marshaller m = ctxt.createMarshaller();
m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
m.marshal(map, System.out);

Unmarshaller um =  MarshalUtils.getUnmarshaller();            
        SchemaFactory sf = SchemaFactory.newInstance(
                javax.xml.XMLConstants.W3C_XML_SCHEMA_NS_URI);
        Schema schema = sf.newSchema(new File(SOURCE_REGION_SCHEMA));
        um.setSchema(schema);

        SourceRegionMap srm = (SourceRegionMap) um.unmarshal(input);

然后将输出保存到x.xml文件中，格式为：

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ns2:sourceCategoryMap xmlns:ns2="http://schemas.xyz.com/services/1.0">
    <ns2:source-category-map>
        <entry>
            <key>Seattle</key>
            <map>
                <entry>
                    <key>Restaurant</key>
                    <value>Restaurant</value>
                </entry>
                <entry>
                    <key>Fun</key>
                    <value>Entertainment</value>
                </entry>
            </map>
        </entry>
        <entry>
            <key>Honolulu</key>
            <map>
                <entry>
                    <key>Food</key>
                    <value>Restaurant</value>
                </entry>
            </map>
        </entry>
    </ns2:source-category-map>
</ns2:sourceCategoryMap>

但它抱怨说：

javax.xml.bind.UnmarshalException
 - with linked exception:
[org.xml.sax.SAXParseException: cvc-elt.1: Cannot find the declaration of element 'ns2:sourceCategoryMap'.]
    at javax.xml.bind.helpers.AbstractUnmarshallerImpl.createUnmarshalException(AbstractUnmarshallerImpl.java:315)

---

有人知道这里出了什么事吗？非常感谢

不要从XML生成XSD。请JAXB使用schemagen命令从java代码生成它。

运行schemagen工具。

javax.xml.bind.UnmarshalException
 - with linked exception:
[org.xml.sax.SAXParseException: cvc-elt.1: Cannot find the declaration of element 'ns2:sourceCategoryMap'.]
    at javax.xml.bind.helpers.AbstractUnmarshallerImpl.createUnmarshalException(AbstractUnmarshallerImpl.java:315)