比如我們有一個實體類：

public class Person {
    private String name;
    private int age;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        
 
this.age = age;
    }
}

得到一個ArrayList

Person person = new Person();
person.setName("a");
person.setAge(1);

Person person1 = new Person();
person1.setName("b");
person1.setAge(2);

List<Person> personList = new ArrayList<>();
personList.add(person);
personList.add(person1);

ArrayList 轉 JSONArray:

JSONArray jsonArray = JSONArray.parseArray(JSON.toJSONString(personList));

JSONArray轉 String:

String str = jsonArray.toJSONString();

String轉 JSONArray:

JSONArray jsonArray1 = JSONArray.parseArray(str);

JSONArray轉 ArrayList:

List<Person> list = JSONObject.parseArray(jsonArray1.toJSONString(), Person.class
 
);