Detailed explanation of JSONObject usage

JSONObject is just a data structure, which can be understood as a data structure in JSON format ( key-value structure). You can use the put method to add elements to the JSON object. JSONObject can be easily converted into a string, and other objects can also be easily converted into JSONObject objects.

pom:

 <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.28</version>
        </dependency>

1. Generate json data format natively.

JSONObject zhangsan = new JSONObject();
        try {
            //Add zhangsan.put("name", "张三");
            zhangsan.put("age", 18.4);
            zhangsan.put("birthday", "1900-20-03");
            zhangsan.put("majar", new String[] {"哈哈","嘿嘿"});
            zhangsan.put("null", null);
            zhangsan.put("house", false);
            System.out.println(zhangsan.toString());
        } catch (JSONException e) {
            e.printStackTrace();
        }

2. Generated through hashMap data structure

     HashMap<String, Object> zhangsan = new HashMap<>();
        
        zhangsan.put("name", "张三");
        zhangsan.put("age", 18.4);
        zhangsan.put("birthday", "1900-20-03");
        zhangsan.put("majar", new String[] {"哈哈","嘿嘿"});
        zhangsan.put("null", null);
        zhangsan.put("house", false);
        System.out.println(new JSONObject(zhangsan).toString());

3. Generate through entities

        Student student = new Student();
        student.setId(1);
        student.setAge("20");
        student.setName("张三");
        //Generate json format System.out.println(JSON.toJSON(student));
        //Convert the object to string
        String stuString = JSONObject.toJSONString(student);

4.Convert JSON string into JSON object

String studentString = "{\"id\":1,\"age\":2,\"name\":\"zhang\"}";
 
//Convert JSON string into JSON object JSONObject jsonObject1 = JSONObject.parseObject(stuString);
 
System.out.println(jsonObject1);

5. Convert list object to listJson

ArrayList<Student> studentLsit = new ArrayList<>();
        Student student1 = new Student();
        student1.setId(1);
        student1.setAge("20");
        student1.setName("asdasdasd");
 
        studentLsit.add(student1);
 
        Student student2 = new Student();
        student2.setId(2);
        student2.setAge("20");
        student2.setName("aaaa:;aaa");
 
        studentLsit.add(student2);
 
        // list to json string String string = JSON.toJSON(studentLsit).toString();
        System.out.println(string);
 
        //Convert json string to listJson format JSONArray jsonArray = JSONObject.parseArray(string);
 
        System.out.println(jsonArray);

Alibaba's json is very easy to use, and Google's Gson is also good. If you are interested, you can take a look

This concludes this article on the detailed usage of JSONObject. I hope it will be helpful for everyone’s study, and I also hope that everyone will support 123WORDPRESS.COM.

You may also be interested in:

Java JSONObject and JSONArray object case study
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Detailed explanation of String JSONObject JSONArray List<entity class> conversion in Java
Analysis of JSONObject and JSONArray usage
Java uses JSONObject to operate json instance parsing
Detailed explanation of the difference between JSONObject and JSONArray in Java
Methods for converting JSON string to JSONObject and JSONArray
Use of JSONObject and JSONArray
Detailed explanation of how to use JSONObject

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