Java JAXB-解组XML文件

我尝试使用以下结构来解组xml文件：

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="map">
    <xs:complexType>
        <xs:sequence>
            <xs:element name="country" maxOccurs="unbounded">
                <xs:complexType>
                    <xs:sequence>
                        <xs:element name="name" type="xs:string" />
                        <xs:element name="x" type="xs:integer" />
                        <xs:element name="y" type="xs:integer" />
                    </xs:sequence>
                </xs:complexType>
            </xs:element>
        </xs:sequence>
        <xs:attribute name="name" type="xs:string" use="required" />
    </xs:complexType>
</xs:element>

及

我总是遇到一个异常，xml似乎不适合创建的POJO。我试着对我读过的一篇教程做同样的练习。此代码行中会出现异常：

 Map map = (Map) unmarsh.unmarshal(file);

你能告诉我需要在POJO中改变什么吗？一切正常

编辑1： 例外情况：

javax.xml.bind.UnmarshalException: unexpected element (uri:"", local:"map"). Expected elements are (none)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext.handleEvent(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.Loader.reportError(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.Loader.reportError(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.Loader.reportUnexpectedChildElement(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext$DefaultRootLoader.childElement(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext._startElement(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext.startElement(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.SAXConnector.startElement(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanStartElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl$NSContentDriver.scanRootElementHook(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal0(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal(Unknown Source)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(Unknown Source)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(Unknown Source)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(Unknown Source)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(Unknown Source)

---

创建

JAXBContext

（用于创建封送拆收器和解封送拆收器实例）时，需要传递模式的根类-通常它们将被标记为

@XmlType

和/或

@XmlRootElement

，以便上下文知道它使用的是哪些类。它没有做的是离开并扫描你的类路径上的所有类，以防它们可能有相关的话要说；那太贵了

实际上，改变：

JAXBContext.newInstance();

致：

---

您可能还需要在注释中明确指定名称空间映射（到空名称空间）（例如，通过

@XmlRootElement

注释的

名称空间

字段），我发现调试JAXB上下文最简单的方法通常是通过

generateSchema

方法生成它们编码的模式（使用一个虚拟输出解析器，它只会导致它们转储到

System.out

…）

您创建的

ObjectFactory

类缺少所需的

@XmlRegistry

注释。如果没有此注释，

ObjectFactory

将被视为常规域对象。

您应该在问题中包含异常。确定了。不确定是否有必要。如何创建

JAXBContext

？JAXBContext jc=JAXBContext.newInstance（“game.view.gui”）；你是如何创建类的？手动？如果正确的话，试着使用jdk的xjc工具。我发现当我使用一组空的绑定类时，我可以准确地重现给出的错误消息。是的，这很有效。但现在我得到了一个例外：IllegalAnnotationExceptions类的计数有两个同名的属性“countries”-但我找不到第二个countries属性-或者我只是不理解exception@baxbear-默认情况下，JAXB希望注释位于属性（get或set方法）上。如果对字段进行注释，则应在类上指定

@xmlacessortype（xmlacesstype.field）

：

package game.view.gui;

import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement(name = "country")
public class Country {
    @XmlElement(required = true)
    private String name;
    @XmlElement(required = true)
    private int x;
    @XmlElement(required = true)
    private int y;

    public String getName() {
        return name;
    }

    public int getX() {
        return x;
    }

    public int getY() {
        return y;
    }
}

 Map map = (Map) unmarsh.unmarshal(file);

javax.xml.bind.UnmarshalException: unexpected element (uri:"", local:"map"). Expected elements are (none)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext.handleEvent(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.Loader.reportError(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.Loader.reportError(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.Loader.reportUnexpectedChildElement(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext$DefaultRootLoader.childElement(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext._startElement(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext.startElement(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.SAXConnector.startElement(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanStartElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl$NSContentDriver.scanRootElementHook(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal0(Unknown Source)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal(Unknown Source)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(Unknown Source)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(Unknown Source)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(Unknown Source)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(Unknown Source)

JAXBContext.newInstance();

JAXBContext.newInstance(Map.class);