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我正在尝试使用 Xstream 从 XML 文件中读取。我遇到的奇怪问题是，当我制作用户列表时，它会正确读取第一个用户，但它会尝试将第二个用户存储为第一个用户的成员变量！我有这个 XML 文件：

<data>
    <users>
        <user>
            <username>test1</username>
            <password>test1</password>
            <firstname>Test</firstname>
            <lastname>One</lastname>
            <email>test1@gmail.com</email>
            <indexedrecords>0</indexedrecords>
        </user>
        <user>
            <username>test2</username>
            <password>test2</password>
            <firstname>Test</firstname>
            <lastname>Two</lastname>
            <email>test2@gmail.com</email>
            <indexedrecords>0</indexedrecords>
        </user>
    </users>
    .... There are other tags here, but they're not causing an issue (yet).
</data>

Xstream 阅读器的代码：

XStream xstream = new XStream(new StaxDriver());
xstream.addImplicitCollection(Model.class, "users", User.class);

@SuppressWarnings("rawtypes")
Class[] classes = new Class[2];
classes[0] = Model.class;
classes[1] = User.class;
xstream.processAnnotations(classes);

String xml = "";//The XML is really stored here, and it does work correctly
xstream.fromXML(xml);

还有课程本身。模型：

@XStreamAlias("data")
public class Model {
    @XStreamImplicit
    public static List<User> users;
    //Other stuff
}

用户：

@XStreamAlias("user")
public class User implements ModelItem{
    private String username;
    private String password;
    @XStreamAlias("firstname")
    private String firstName;
    @XStreamAlias("lastname")
    private String lastName;
    private String email;
    @XStreamAlias("indexedrecords")
    private int recordsIndexed;
}

例外（请原谅[java]- 它正在使用 ANT 运行）：

 [java] Exception in thread "main" com.thoughtworks.xstream.converters.ConversionException: Element user of type shared.model.User is not defined as field in type shared.model.User
 [java] ---- Debugging information ----
 [java] class               : shared.model.User
 [java] required-type       : shared.model.User
 [java] converter-type      : com.thoughtworks.xstream.converters.reflection.ReflectionConverter
 [java] path                : /data/users/user
 [java] line number         : 19
 [java] class[1]            : indexer.shared.model.Model
 [java] version             : null
 [java] -------------------------------
 [java]     at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.writeValueToImplicitCollection(AbstractReflectionConverter.java:403)
 [java]     at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doUnmarshal(AbstractReflectionConverter.java:334)
 [java]     at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:234)
 [java]     at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
 [java]     at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
 [java]     at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
 [java]     at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
 [java]     at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doUnmarshal(AbstractReflectionConverter.java:322)
 [java]     at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:234)
 [java]     at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
 [java]     at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
 [java]     at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
 [java]     at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
 [java]     at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:134)
 [java]     at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:32)
 [java]     at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1052)
 [java]     at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1036)
 [java]     at com.thoughtworks.xstream.XStream.fromXML(XStream.java:912)
 [java]     at com.thoughtworks.xstream.XStream.fromXML(XStream.java:903)
 [java]     at importer.Importer.importXml(Importer.java:77)
 [java]     at importer.Importer.main(Importer.java:45)

为什么 Xstream 试图将第二个User作为变量存储在第一个中User？

答案编辑： 有两个问题，都在迈克尔的回答中得到解决。

1）我暗示了一个我不应该做的隐式集合（两次！），因为 XML 显式声明了一个users列表。

2）我在课堂上的变量Model是静态的。目前尚不清楚为什么这会导致错误，但确实会导致错误。

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1 回答 1

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用户列表之前的@XStreamImplicit注释告诉 XStream，XML 不会有标签调用用户，而是所有称为用户的标签都应该存储在用户列表中。

users从 XML 中删除或从变量声明中删除注释@XStreamImplicit。

其他更改您还需要删除对的调用，xstream.addImplicitCollection(Model.class, "users", User.class);因为它正在执行类似于@XStreamImplicit.

修复隐式后遇到的另一个问题是模型类中的用户变量被声明为静态引起的。由于它是静态的，因此不被视为序列化的一部分。

于 2013-11-07T19:07:40.300 回答