fastjson2 elegant conversion

Common types

Type 1: JavaBean

Type 2: List

Type 3: List

Type 4: List<Map<String, Object>>

The method of converting the above four data objects into json strings is the same

String jsonString = JSON.toJSONString(obj);

Tools/Materials

fastjson2

method/step

1. Convert json string to JavaBean object

Person person = new Person(“1”,“fastjson”,1);

2. Here the javabean is converted into a json string

String jsonString = JSON.toJSONString(person);

3. Here the json string is converted into a javabean object,

person =JSON.parseObject(jsonString,Person.class);

4. Convert json string to List object

Person person1 = new Person(“1”,“fastjson1”,1);

Person person2 = new Person(“2”,“fastjson2”,2);

List persons = new ArrayList();

persons.add(person1);

persons.add(person2);

String jsonString = JSON.toJSONString(persons);

System.out.println("json string: "+jsonString);

5. parse json string

List persons2 = JSON.parseArray(jsonString,Person.class);

6. Convert json string to List object

List list = new ArrayList();

list.add(“fastjson1”);

list.add(“fastjson2”);

list.add(“fastjson3”);

String jsonString = JSON.toJSONString(list);

System.out.println("json string: "+jsonString);

7. parse json string

List list2 = JSON.parseObject(jsonString,new TypeReference<List>(){});

Convert json string to List<Map<String, Object>> object

Map<String,Object> map = new HashMap<String,Object>();

map.put(“key1”, “value1”);

map.put(“key2”, “value2”);

Map<String,Object> map2 = new HashMap<String,Object>();

map2.put(“key1”, 1);

map2.put(“key2”, 2);

List<Map<String,Object>> list = new ArrayList<Map<String,Object>>();

list.add(map);

list.add(map2);

String jsonString = JSON.toJSONString(list);

System.out.println("json string: "+jsonString);

8. parse json string

List<Map<String,Object>> list2 = JSON.parseObject(jsonString,new TypeReference<List<Map<String,Object>>>(){});