使用 Jackson Java 反序列化具有没有值的属性的 XML 元素

Question

我正在尝试反序列化以下内容 XML 但我无法反序列化参数参数部分。

<video src="https://google.com/sample.mp4">
    <param>s</param>
    <param>Y</param>
    <param>Z</param>
</video>

我的模型

import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlElementWrapper;
import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlProperty;

import java.util.ArrayList;
import java.util.List;

public class Video {
    @JacksonXmlProperty(isAttribute = true)
    private String src;

    @JacksonXmlElementWrapper(localName = "param", useWrapping = false)
    private List<String> param = new ArrayList<>();

    public String getSrc() {
        return src;
    }

    public List<String> getParam() {
        return param;
    }

    public void setParam(List<String> param) {
        this.param = param;
    }
}

输出

{
    "src": "https://google.com/sample.mp4",
    "param": [
        "Z"
    ]
}

我希望 param 的值类似于

{
    "src": "https://google.com/sample.mp4",
    "param": [
        "s",
        "Y",
        "Z"
    ]
}

Java代码

ObjectMapper mapper = new ObjectMapper(new XmlFactory());
mapper.enable(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY);
Video video = mapper.readValue(s, Video.class);
System.out.println(new ObjectMapper(new JsonFactory()).writeValueAsString(video));

谁能帮我让它工作。谢谢。

Answer 1

我使用了以下代码并且对我有用，

XmlMapper mapper = new XmlMapper();
    mapper.enable(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY);
    Video video = mapper.readValue(s, Video.class);
    System.out.println(new ObjectMapper(new JsonFactory()).writeValueAsString(video));

XmlMapper 来自包 com.fasterxml.jackson.dataformat.xml.XmlMapper

希望对你有所帮助。

Answer 2

您需要使用：

@JacksonXmlProperty(localName = "param")
@JacksonXmlElementWrapper(useWrapping = false)
private List<String> param = new ArrayList<>();

并删除 mapper.enable(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY);，因为它只会掩盖问题。

这段代码对我有用：

XmlMapper mapper = new XmlMapper();
Video video = mapper.readValue(s, Video.class);
System.out.println(new ObjectMapper(new JsonFactory()).writeValueAsString(video));

输出： {"src":"https://google.com/sample.mp4","param":["s","Y","Z"]}

使用 Jackson Java 反序列化具有没有值的属性的 XML 元素

Deserialize XML element with attributes with no value using Jackson Java

java

jackson

jackson-dataformat-xml

jackson-databind