Jackson XML is directly converted to JSON without writing entity classes manually

  Warning ： At present, tests on different computers are not very stable , I am glad that the test was successful , Sometimes Chinese garbled code appears （idea Tool configuration related ）, Another serious problem is When parsing a with an array xml when , Elements of the same type in the array will be treated as a parse , Cause incomplete data , As in this example student object ;

reason ：springboot The version of is too low , requirement 2.4.5 above ;fastjson There are also such problems , So it's not recommended here , If the inspector insists on using fastjson, It can be provided by the owner 1.2.76, As if 1.2.75 It's fine too , Forget the .

There can be another way , Is to introduce org.json rely on , Use   XML.toJSONObject(String xml) Method , Analytic logic is the same as the first pure   jackson The writing is similar , The code is a bit long but not complicated , If you find a problem, you can raise it , I will follow up .

A pit ： When springboot The dependent version of the parent project is 2.4.5 when

JsonNode jsonNode = xmlMapper.readValue(newXML, JsonNode.class); The breakpoint result is shown in the following figure

It is also written like this JsonNode jsonNode = xmlMapper.readValue(newXML, ObjectNode.class);

We can know from the source code ,ObjectNode yes JsonNod Derived inheritance classes .

Test the successful dependent version ：

<?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>com.jt</groupId>
    <artifactId>springboot_demo_4</artifactId>
    <version>1.0-SNAPSHOT</version>

    <!-- Import parent project -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.0</version>
        <relativePath/>
    </parent>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <!--thymeleaf Import template tool class -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>

        <!--SpringMVCjar Package file -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- Hot deployment tools -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <!--lombok plug-in unit -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

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

        <!-- introduce jdbc package -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>

        <!-- Introduce database driver  -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

        <!--spring Integrate mybatis-plus -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.4.2</version>
        </dependency>

        <!--fastjson-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.76</version>
        </dependency>

        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.13</version>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.1</version>
            <scope>test</scope>
        </dependency>

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

        <!-- https://mvnrepository.com/artifact/org.json/json -->
        <dependency>
            <groupId>org.json</groupId>
            <artifactId>json</artifactId>
            <version>20180813</version>
        </dependency>

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.0</version>
        </dependency>

    </dependencies>

    <!-- Responsible for project packaging and deployment -->
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

package com.jt.test;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.fasterxml.jackson.dataformat.xml.XmlMapper;
import org.apache.commons.lang3.StringUtils;
import org.json.XML;

import java.util.HashMap;
import java.util.Map;

/**
 * User: ldj
 * Date: 2022/1/26
 * Time: 21:24
 * Description: xml Go straight to json
 */
public class XmlToJsonDemo {
    public static void main(String[] args) {

        // Object turn xml
        String xml = "<Message>" +
                "        <School>" +
                "               <SchoolName> Straw hat middle school </SchoolName>" +
                "        </School>" +
                "        <Class>" +
                "               <ClassName> three 7 class </ClassName>" +
                "               <Level>" +
                "                    <A>1</A>" +
                "                    <B>2</B>" +
                "               </Level>" +
                "               <Person>" +
                "                       <Teacher>" +
                "                              <Name>LuLu</Name>" +
                "                              <Gender> Woman </Gender>" +
                "                              <Age>23</Age>" +
                "                       </Teacher>" +
                "                       <Student>" +
                "                              <Name> Zhang San </Name>" +
                "                              <Gender> male </Gender>" +
                "                              <Age>16</Age>" +
                "                      </Student>" +
                "                       <Student>" +
                "                              <Name> Li Si </Name>" +
                "                              <Gender> male </Gender>" +
                "                              <Age>17</Age>" +
                "                      </Student>" +
                "                       <Student>" +
                "                              <Name> lily </Name>" +
                "                              <Gender> Woman </Gender>" +
                "                              <Age>16</Age>" +
                "                      </Student>" +
                "               </Person>" +
                "        </Class>" +
                "</Message>";

        String age = "18";
        int ages = Integer.parseInt(age);
        System.out.println(ages);


        System.out.println("\n");
        System.out.println("=============================== xml -> json  Node by node analysis ================================");

        Map<String, String> responseMap = xmlToJson(xml);
        String schoolJSON = responseMap.get("schoolJSON");
        String classJSON = responseMap.get("classJSON");
        System.out.println(schoolJSON);
        System.out.println(classJSON);

        System.out.println("\n");
        System.out.println("=============================== xml -> json  Full node resolution ================================");

        System.out.println(getResponseJSON(xml, "Message"));

        System.out.println("\n");
        System.out.println("=================================org.json  Node by node analysis ==========================================");

        Map<String, String> responseMap1 = xml2Json(xml, "Message");
        String schoolJSON1 = responseMap1.get("schoolJSON");
        String classJSON1 = responseMap1.get("classJSON");

        System.out.println(schoolJSON1);
        System.out.println(classJSON1);
        System.out.println("\n");

    }

    // Node by node resolution 
    private static Map<String, String> xmlToJson(String xml) {
        XmlMapper xmlMapper = new XmlMapper();
        HashMap<String, String> responseMap = new HashMap<>();
        try {
            JsonNode jsonNode = xmlMapper.readValue(xml, JsonNode.class);

            JsonNode schoolNode = jsonNode.get("School");
            JsonNode classNode = jsonNode.get("Class");

            ObjectMapper objectMapper = new ObjectMapper();

            if (schoolNode.isContainerNode()) {
                String schoolJSON = objectMapper.writeValueAsString(schoolNode);
                if (StringUtils.isNotBlank(schoolJSON)) {
                    responseMap.put("schoolJSON", schoolJSON);
                }
            }

            if (classNode.isContainerNode()) {
                String classJSON = objectMapper.writeValueAsString(classNode);
                if (StringUtils.isNotBlank(classJSON)) {
                    responseMap.put("classJSON", classJSON);
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return responseMap;
    }

    // Analyze all 
    private static String getResponseJSON(String xml, String rootTag) {

        // Right in xml Add the root node label <Tag></Tag>
        String s1 = "<" + rootTag + ">";
        String s2 = "</" + rootTag + ">";

        StringBuilder sb = new StringBuilder(xml.replaceAll("\\s*", ""));

        int indexStart = sb.indexOf(s1);
        sb.insert(indexStart + (s1.length()), "<Tag>");

        int indexEnd = sb.indexOf(s2);
        sb.insert(indexEnd, "</Tag>");

        String newXML = sb.toString();
        String responseJSON = null;

        XmlMapper xmlMapper = new XmlMapper();
        try {
            //JsonNode jsonNode = xmlMapper.readValue(newXML, JsonNode.class);
            JsonNode jsonNode = xmlMapper.readValue(newXML, ObjectNode.class);

            JsonNode schoolNode = jsonNode.get("Tag");

            ObjectMapper objectMapper = new ObjectMapper();

            if (schoolNode.isContainerNode()) {
                String json = objectMapper.writeValueAsString(schoolNode);
                if (StringUtils.isNotBlank(json)) {
                    responseJSON = json;
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return responseJSON;
    }

    // Use org.json +  jackson package   perhaps  org.json +  fastjson package < Not recommended >
    private static Map<String, String> xml2Json(String xml, String rootTag) {

        HashMap<String, String> responseMap = new HashMap<>();

        // Remove the root tag Message, If you don't remove the root tag Message, The generated data structure is "Message":{.....}
        if (StringUtils.isNotBlank(rootTag)) {
            xml = xml.replace("<" + rootTag + ">", "");
            xml = xml.replace("</" + rootTag + ">", "");
        }

        try {
            org.json.JSONObject json = XML.toJSONObject(xml);

            /**
             *  Due to version issues , When parsing a with an array xml when , Treat elements of the same type in the array as a parse , Cause incomplete data , Still use the original jackson package 
             * com.alibaba.fastjson.JSONObject jsonObject = com.alibaba.fastjson.JSONObject.parseObject(json.toString());
             * String schoolNode = jsonObject.getString("School");
             * String classNode = jsonObject.getString("Class");
             */

            /*
             *  In fact, the first method above   XmlMapper()  Is inherited  ObjectMapper 《 Source code 》  So the following two lines of code are equivalent to 
             * XmlMapper xmlMapper = new XmlMapper();
             * JsonNode jsonNode = xmlMapper.readValue(xml, JsonNode.class);
             * ObjectNode yes JsonNod  Derived inheritance classes 
             */

            ObjectMapper objectMapper = new ObjectMapper();
            JsonNode jsonNode = objectMapper.readValue(json.toString(), JsonNode.class);

            if (jsonNode.isContainerNode()) {

                JsonNode schoolNode = jsonNode.get("School");
                JsonNode classNode = jsonNode.get("Class");

                if (schoolNode.isContainerNode()) {
                    responseMap.put("schoolJSON", schoolNode.toString());
                }

                if (classNode.isContainerNode()) {
                    responseMap.put("classJSON", classNode.toString());
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return responseMap;
    }
}

    //jason  It can also be read as Tree, I don't know that the performance will remain high , Never tested 
    private static HashMap<String, String> getResponseTree(String xml){

        XmlMapper xmlMapper = new XmlMapper();
        HashMap<String, String> responseMap = new HashMap<>();

        try {
            JsonNode jsonNode = xmlMapper.readTree(xml.getBytes(StandardCharsets.UTF_8));

            if(jsonNode.isContainerNode()){

                JsonNode schoolNode = jsonNode.get("School");
                JsonNode classNode = jsonNode.get("Class");

                ObjectMapper objectMapper = new ObjectMapper();

                if (schoolNode.isContainerNode()) {
                    //responseMap.put("schoolJSON", schoolNode.toString());
                    String schoolJSON = objectMapper.writeValueAsString(schoolNode);
                    if (StringUtils.isNotBlank(schoolJSON)) {
                        responseMap.put("schoolJSON", schoolJSON);
                    }
                }

                if (classNode.isContainerNode()) {
                    String classJSON = objectMapper.writeValueAsString(classNode);
                    if (StringUtils.isNotBlank(classJSON)) {
                        responseMap.put("classJSON", classJSON);
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return responseMap;
    }

 

  I want the number type and I use the first way , What do I do ？

        String age = "18";
        int ages = Integer.parseInt(age);
        System.out.println(ages);

Use org.json

        <!-- https://mvnrepository.com/artifact/org.json/json -->
        <dependency>
            <groupId>org.json</groupId>
            <artifactId>json</artifactId>
            <version>20180813</version>
        </dependency>


    private static String xtj(String xml) {
        JSONObject json = XML.toJSONObject(xml);
        return json.toString();
    }

If there is Chinese garbled code, you can set it like this