是否可以使用JAXB从模式映射到java.util.Map？ [英] Is it possible to use JAXB to map from schema to a java.util.Map?

问题描述

我有一个现有的XML模式，它包含一个我希望使用JAXB映射到某种Java Map的类型。我的构建过程采用模式并创建bean。我想通过将我的架构映射中的一个complexTypes映射到java.util.Map来自定义此过程。我读过JAXB无法做接口的地方。我不确定这是否适用于这种情况，但如果是这样我可以将它映射到HashMap。此外，它不一定必须是映射到Map的complexType，如果需要的话，它可能是一个元素。

I have an existing XML schema that contains a type that I would like to map to a Java Map of some sort using JAXB. My build process takes the schema and creates the beans. I would like to customize this process by having one of the complexTypes in my schema map to a java.util.Map. I've read somewhere that JAXB "can't do interfaces." I'm not sure if that applies in this case, but if so I'd be fine with it mapping to a HashMap. Also, it doesn't necessarily have to be the complexType that maps to a Map, it could be an element if that's what's required.

我使用a控制我的JAXB生成.xjb文件，所以我正在寻找一些< jaxb：bindings> 来放入。我尝试了以下方法，但它不起作用：

I control my JAXB generation using a .xjb file, so I'm looking for some <jaxb:bindings> to put in there. I've tried the following, but it does not work:

<jaxb:bindings schemaLocation="myschema.xsd" node="/xs:schema">
    <jaxb:globalBindings>
        <jaxb:serializable uid="1"/>
    </jaxb:globalBindings>
    <jaxb:schemaBindings>
        <jaxb:package name="com.myschema.client.types"/>
    </jaxb:schemaBindings>
    <jaxb:bindings node="//xs:complexType[@name='MapType']">
            <jaxb:javaType name="java.util.HashMap"
            parseMethod="com.myschema.common.MapConverter.parseObjectToMap"
            printMethod="com.myschema.common.MapConverter.printMapToObject" />
    </jaxb:bindings>
</jaxb:bindings>

编辑：我在上面的绑定中添加了更多细节我已经尝试过了。它在模式编译期间生成以下错误：

I've added more detail on the above binding that I've already tried. It generates the following error during schema compile:

[jaxb] [ERROR] compiler was unable to honor this javaType customization. It is attached to a wrong place, or its inconsistent with other bindings.

---

< jaxb： javaType> 无效，因为它只能用于 XML Schema原语和Java类型之间的映射。由于我想在复杂类型和Java类型之间进行映射，我不能使用它。

---

<jaxb:javaType> will not work because it can only be used for mapping between XML Schema primitives and Java types. Since I want to map between a complex type and a Java type, I cannot use this.

推荐答案

您的XJC文件正在使用standard javaType 指令，我认为它仅限于将String值转换为代表性的java类型。因此，它仅适用于转换简单元素和属性内容。

Your XJC file is using the "standard" javaType directive, which I believe is limited to converting String values to and from a representative java type. As such, it's only suitable for converting simple element and attribute content.

XJC工具提供 javaType ，理论上应该能够处理更复杂的结构。不幸的是，这还没有实现：

The XJC tool provides an enhanced version of javaType, which in theory should be able to handle more complex structures. Unfortunately, this has yet to be implemented:

https://java.net/jira/browse/JAXB-209 （未解决）

例如，能够将
模式类型映射到HashMap对于那些使用
模型驱动设计/实现的人来说可能需要
。
AFAICS，今天不可能。
因此，必须手动编辑
生成的代码。

For instance, being able to map a schema type to a HashMap might be a likely requirement for those using model driven design/implementation. AFAICS, this is not possible today. Therefore, one must manually edit the generated code.

看起来你运气不好。

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