JAVA XML转对象对象转XML

今天药忘吃喽~ 2022-05-10 12:56 427阅读 0赞

在网上看了许多XML跟Obj互相转换的Demo，但是都很复杂，现在推荐一个极度简单好理解的XML和Obj互转的例子：

JacksonXML，只需要简单的几个注解就能完成XML和Obj的相互转换

假设有如下xml报文：

<?xml version="1.0" encoding="utf-8"?>
    <msgbody>
      <StringList>
        <mx>
          <paramA>Aone</paramA>
          <paramB>Bone</paramB>
        </mx>
        <mx>
          <paramA>Atow</paramA>
          <paramB>Atow</paramB>
        </mx>
      </StringList>
      <serverId>serv10000000156</serverId>
      <name>张三</name>
      <age>女</age>
      <address>武汉市</address>
    </msgbody>

分析这段报文，首先报文头是 <?xml version="1.0" encoding="utf-8"?>

然后有<msgbody>标签包住报文体，然后有属性serverId，name，age，address 和 一个列表，列表中的每一个单位用<mx>标签分隔开来，最后每个单位中都有paramA 和 paramB 两个属性。

准备工作添加pom依赖：

<dependency>
    	<groupId>com.fasterxml.jackson.dataformat</groupId>
    	<artifactId>jackson-dataformat-xml</artifactId>
    	<version>2.9.0</version>
    </dependency>
    <dependency>
    	<groupId>com.fasterxml.woodstox</groupId>
    	<artifactId>woodstox-core</artifactId>
    	<version>5.1.0</version>
    </dependency>

那么第一步我们创建与这个报文对应的class：

package com.symphony.springbootdata.demo.xmlTest;
    
    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 java.util.List;
    
    /**
     * 报文对应class
     *
     * @author <a href="***@163.com">***</a>
     * @version 1.0.0
     * @since 1.0.0
     * <p>
     * Created at 2018/9/30
     */
    
    @JacksonXmlRootElement(localName = "msgbody")
    public class Person {
        @JacksonXmlProperty(localName = "serverId")
        private String serverId;
        @JacksonXmlProperty(localName = "name")
        private String name;
        @JacksonXmlProperty(localName = "age")
        private String age;
        @JacksonXmlProperty(localName = "address")
        private String address;
        @JacksonXmlElementWrapper(localName = "StringList")
        private List<Clazz> mx;
    
        public Person() {
        }
    
        public Person(String serverId, String name, String age, String address, List<Clazz> mx) {
            this.serverId = serverId;
            this.name = name;
            this.age = age;
            this.address = address;
            this.mx = mx;
        }
    
        public String getServerId() {
            return serverId;
        }
    
        public void setServerId(String serverId) {
            this.serverId = serverId;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public String getAge() {
            return age;
        }
    
        public void setAge(String age) {
            this.age = age;
        }
    
        public String getAddress() {
            return address;
        }
    
        public void setAddress(String address) {
            this.address = address;
        }
    
        public List<Clazz> getMx() {
            return mx;
        }
    
        public void setMx(List<Clazz> mx) {
            this.mx = mx;
        }
    
        @Override
        public String toString() {
            return "Person{" +
                    "serverId='" + serverId + '\'' +
                    ", name='" + name + '\'' +
                    ", age='" + age + '\'' +
                    ", address='" + address + '\'' +
                    ", mx=" + mx +
                    '}';
        }
    }

package com.symphony.springbootdata.demo.xmlTest;
    
    import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlProperty;
    import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlRootElement;
    
    /**
     * 报文中列表对应class
     *
     * @author <a href="***@163.com">***</a>
     * @version 1.0.0
     * @since 1.0.0
     * <p>
     * Created at 2018/10/9
     */
    @JacksonXmlRootElement(localName = "MX")
    public class Clazz {
        @JacksonXmlProperty(localName = "paramA")
        private String a;
        @JacksonXmlProperty(localName = "paramB")
        private String b;
    
        public String getA() {
            return a;
        }
    
        public void setA(String a) {
            this.a = a;
        }
    
        public String getB() {
            return b;
        }
    
        public void setB(String b) {
            this.b = b;
        }
    
        @Override
        public String toString() {
            return "Clazz{" +
                    "a='" + a + '\'' +
                    ", b='" + b + '\'' +
                    '}';
        }
    }

创建好对应的class之后，开始XML与Obj的转换

package com.symphony.springbootdata.demo.xmlTest;
    
    import com.fasterxml.jackson.core.JsonProcessingException;
    import com.fasterxml.jackson.databind.ObjectMapper;
    import com.fasterxml.jackson.dataformat.xml.XmlMapper;
    import org.junit.Test;
    
    import javax.xml.bind.JAXBException;
    import java.io.IOException;
    import java.util.ArrayList;
    import java.util.List;
    
    /**
     * XML Obj 互相转换
     *
     * @author <a href="mailto:***@163.com">***</a>
     * @version 1.0.0
     * @since 1.0.0
     * <p>
     * Created at 2018/9/30
     */
    public class ObjToXmlUtils {
    
        public static void main(String[] args) throws JsonProcessingException {
            List<Clazz> mx = new ArrayList<>();
            Clazz clazz = new Clazz();
            clazz.setA("Aone");
            clazz.setB("Bone");
            mx.add(clazz);
            clazz = new Clazz();
            clazz.setA("Atow");
            clazz.setB("Atow");
            mx.add(clazz);
    
            ObjectMapper mapper = new XmlMapper();
            String s = mapper.writeValueAsString(new Person("serv10000000156", "张三", "女", "武汉市", mx));
            System.out.println("<?xml version=\"1.0\" encoding=\"utf-8\"?>" + s);
        }
    
        @Test
        public void xmlToObj() throws JAXBException, IOException {
            String xml = "<?xml version=\"1.0\" encoding=\"utf-8\"?><msgbody><StringList><mx><paramA>Aone</paramA><paramB>Bone</paramB></mx><mx><paramA>Atow</paramA><paramB>Atow</paramB></mx></StringList><serverId>serv10000000156</serverId><name>张三</name><age>女</age><address>武汉市</address></msgbody>\n";
            ObjectMapper mapper = new XmlMapper();
            Object po = null;
            po = mapper.readValue(xml, Person.class);
            System.out.println(po.toString());
        }
    }

综上，我们看到了注解

@JacksonXmlElementWrapper：指定用于包装List和Map属性的XML元素  
　@JacksonXmlProperty：为属性指定XML名称空间和本地名称; 以及是否将属性写为XML元素或属性  
　@JacksonXmlRootElement：指定用于包装根元素的XML元素  
　@JacksonXmlText：指定当前这个值，没有xml标签包裹