Jackson XMLWrapper 未能将此 xml 反序列化为 pojo?

问题描述:

考虑下面给定的 xml:

Consider the given xml below:

<?xml version="1.0"?>
<Records>
    <Record>
        <Prop name="commerce">sku1</Prop>
        <Prop name="commerce">sku2</Prop>
        <Prop name="commerce">sku3</Prop>
        <Prop name="commerce">sku4</Prop>
    </Record>
    <Record>
        <Prop name="commerce">sku10</Prop>
        <Prop name="commerce">sku20</Prop>
        <Prop name="commerce">sku30</Prop>
        <Prop name="commerce">sku40</Prop>
    </Record>
</Records>

现在考虑我创建的这些 Pojo(为了简洁起见,删除了 getter 和 setter).

Now consider these Pojos that I have created(removing getter and setters for brevity).

public class Records {
    private List<Record> records;
}

public class Record {
    private List<Prop> props;
}

public class Prop {
    // I want to capture name attribute
    private String name;
    // But I also want to capture what comes inside Prop element as well. This would then have values like sku1, sku2 etc
    private String text;
}

现在我有像这样使用 XMLWrapper 的代码.

Now I have code using XMLWrapper like this.

File file = ResourceUtils.getFile("classpath:sample.xml"); // the above XML is sample.xml
XmlMapper xmlMapper = XmlMapper.builder().build();
Records records = xmlMapper.readValue(file, Records.class); // this line is failing

但我收到这样的错误

Caused by: com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "Record" (class com.example.demo.model.xml.Records), not marked as ignorable (one known property: "records"])

你必须结合 @JacksonXmlProperty 注释,带有 @JacksonXmlElementWrapper 注释表示要与 Collection 一起使用的包装元素:在这种情况下,可选属性 useWrapping 设置为 false 以显式禁用包装:

You have to combine the @JacksonXmlProperty annotation with the @JacksonXmlElementWrapper annotation that indicates the wrapper element to use with a Collection: in this case the optional property useWrapping is set to false to explicitly disable the wrapping:

public class Records {
    @JacksonXmlProperty(localName = "Record")
    @JacksonXmlElementWrapper(useWrapping = false)
    private List<Record> records;
}

public class Record {
    @JacksonXmlProperty(localName = "Prop")
    @JacksonXmlElementWrapper(useWrapping = false)
    private List<Prop> props;
}

public class Prop {
    //<Prop name="commerce">sku1</Prop> name is an attribute with value commerce
    @JacksonXmlProperty(localName= "name", isAttribute = true)
    private String name;
    
    //<Prop name="commerce">sku1</Prop> sku1 is the text inside the Prop tags
    @JacksonXmlText
    private String text;
}