Jackson 反序列化XML

反序列化 XML

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>untitled1</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.4.RELEASE</version>
    </parent>

    <dependencies>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.dataformat</groupId>
            <artifactId>jackson-dataformat-xml</artifactId>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>

    </dependencies>

</project>

users.xml

<users>
    <user id="1">
        <name>张三</name>
        <age>25</age>
    </user>
    <user id="2">
        <name>李四</name>
        <age>30</age>
    </user>
</users>

UserList.java

package org.example;

import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlElementWrapper;
import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlProperty;
import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlRootElement;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.util.List;

// 根节点（可选，流式解析时可省略）
@Data
@NoArgsConstructor
@JacksonXmlRootElement(localName = "users")
public class UserList {

    @JacksonXmlElementWrapper(useWrapping = false)
    @JacksonXmlProperty(localName = "user")
    private List<User> users;

    // 无参构造器 + getter/setter
}

User.java

package org.example;

import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlProperty;
import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlRootElement;
import lombok.Data;
import lombok.NoArgsConstructor;

// 单个用户节点
@Data
@NoArgsConstructor
@JacksonXmlRootElement(localName = "user")
public class User {
    @JacksonXmlProperty(isAttribute = true) // 映射 XML 属性（id="1"）
    private Long id;
    @JacksonXmlProperty // 映射 XML 子节点
    private String name;
    @JacksonXmlProperty
    private Integer age;

    // 无参构造器（Jackson 必须）+ getter/setter

    // 省略 getter/setter
}

Xml2ObjectTest2.java

package org.example;

import com.fasterxml.jackson.dataformat.xml.XmlMapper;
import org.junit.jupiter.api.Test;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;

public class Xml2ObjectTest2 {

    @Test
    public void whenJavaSerializedToXmlFile_thenCorrect() throws IOException {

        XmlMapper xmlMapper = new XmlMapper();

        UserList userList;
        File file2 = new File("E:\\record\\2025\\12\\5\\users.xml");

        userList = xmlMapper.readValue(file2, UserList.class);
        System.out.println(userList);

        FileInputStream fis = new FileInputStream(file2);
        // 传入文件流 + 目标类型
        userList = xmlMapper.readValue(fis, UserList.class);
        System.out.println(userList);

    }

}