XmlRootElement的作用和用法

手动封装实体类转换成xml

实体类

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;

/**
 * @ClassName RequetsXml
 * @Description TODO
 * @Author xiongchao
 * @Date 2020/7/14 10:23
 **/

@XmlRootElement(name = "request")
public class RequetsXml {

    @XmlElement(name = "casefile")
    private CaseFile caseFile;

    @XmlElement(name = "uploaded-file-id")
    private String fileId;

    public void setCaseFile(CaseFile caseFile) {
        this.caseFile = caseFile;
    }

    public void setFileId(String fileId) {
        this.fileId = fileId;
    }

    private static class CaseFile{

        private String name;

        @XmlElement(name = "isTmpFile")
        private boolean isTmpFile;

        @XmlElement(name = "modify-timestamp")
        private String modifyTimStamp;

        @XmlElement(name = "sdb-group-id")
        private Integer groupId;

        @XmlElement(name = "source-system-id")
        private Integer sourceId;

        public void setName(String name) {
            this.name = name;
        }

        public void setTmpFile(boolean tmpFile) {
            isTmpFile = tmpFile;
        }

        public void setModifyTimStamp(String modifyTimStamp) {
            this.modifyTimStamp = modifyTimStamp;
        }

        public void setGroupId(Integer groupId) {
            this.groupId = groupId;
        }

        public void setSourceId(Integer sourceId) {
            this.sourceId = sourceId;
        }
    }

测试

public static void main(String[] args) throws JAXBException {
        RequetsXml root = new RequetsXml();
        root.setFileId("adsa45475454");

        CaseFile caseFile = new CaseFile();
        caseFile.setName("王凯");
        caseFile.setTmpFile(false);
        caseFile.setGroupId(1);
        caseFile.setSourceId(0);
        caseFile.setModifyTimStamp("1575454212");
        root.setCaseFile(caseFile);

        JAXBContext context = JAXBContext.newInstance(RequetsXml.class);
        Marshaller m = context.createMarshaller();
        m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
        m.marshal(root, System.out);

    }

输出

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<request>
    <casefile>
        <name>王凯</name>
        <isTmpFile>false</isTmpFile>
        <modify-timestamp>1575454212</modify-timestamp>
        <sdb-group-id>1</sdb-group-id>
        <source-system-id>0</source-system-id>
    </casefile>
    <uploaded-file-id>adsa45475454</uploaded-file-id>
</request>

工具类封装

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import org.json.JSONException;
import org.json.XML;

import java.io.StringReader;
import java.io.StringWriter;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;

/**
 *
 * Class Name: XmlConvertUtil
 * Description: xml格式转化工具类
 *
 */
public class XmlConvertUtil {
    /**
     * xml转换成JavaBean
     *
     * @param xml xml格式字符串
     * @param t 待转化的对象
     * @return 转化后的对象
     * @throws Exception JAXBException
     */
    @SuppressWarnings({ "unchecked" })
    public static <T> T convertToJavaBean(String xml, Class<T> t) throws Exception {
        T obj = null;
        JAXBContext context = JAXBContext.newInstance(t);
        Unmarshaller unmarshaller = context.createUnmarshaller();
        obj = (T) unmarshaller.unmarshal(new StringReader(xml));
        return obj;
    }

    /**
     * JavaBean转换成xml
     * @param obj
     * @param encoding
     * @return
     */
    public static String convertToXml(Object obj, String encoding) {
        String result = null;
        try {
            JAXBContext context = JAXBContext.newInstance(obj.getClass());
            Marshaller marshaller = context.createMarshaller();
            marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
            marshaller.setProperty(Marshaller.JAXB_ENCODING, encoding);

            StringWriter writer = new StringWriter();
            marshaller.marshal(obj, writer);
            result = writer.toString();
        } catch (Exception e) {
            e.printStackTrace();
        }

        return result;
    }

    public static JSONObject xmlToJson(String xml) {
        try {
            org.json.JSONObject object = XML.toJSONObject(xml);
            String jsonData = object.get("response").toString();
            JSONObject jsonObject = JSON.parseObject(jsonData);
            return jsonObject;
            /*JSONObject result = (JSONObject) jsonObject.get("result");
            JSONObject upload = (JSONObject) result.get("upload");
            String uploadUrl = upload.get("url").toString();
            String fildId = upload.get("upload-file-id").toString();*/
        } catch (JSONException e) {
            e.printStackTrace();
            return null;
        }
    }
}

切记,实体类中的@XmlRootElement注解不可一省略,否则会抛异常

[特别重要] 补充一下,加上get方法之后,如果出现报错,在get方法上面添加注解@XmlTransient

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