Java笔记-FastJson中JsonObject、JsonA

FastJson是阿里开源的JSON库

Maven引入包依赖

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.37</version>
</dependency>

JSONObject

---

相互转化关系图

• JavaBean

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

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

• JSONStr

{"age":20,"name":"xiaoming"}

• JSONObject

{
    "age": 20,
    "name": "xiaoming",
}

Demo

1. JSONObject转JSONStr

public void test() {
        JSONObject object = new JSONObject();
        object.put("age", 20);
        object.put("name", "xiaoming");
        String str = JSON.toJSONString(object);
    }

2. JSONStr转JSONObject

public void test() {
        String str = "{\"sex\":\"male\",\"name\":\"xiaoming\",\"age\":20}";
        JSONObject object = JSON.parseObject(str);
    }

3. JSONStr转JavaBean

public void test() {
        String str = "{\"sex\":\"male\",\"name\":\"xiaoming\",\"age\":20}";
        Person person = JSON.parseObject(str, Person.class);
    }

4. JavaBean转JSONStr

public void test() {
        Person person = new Person(20, "xiaoming");
        String str = JSON.toJSONString(person);
    }

5. JavaBean转JSONObject

public void test() {
        Person person = new Person(20, "xiaoming");
        JSONObject object = (JSONObject) JSON.toJSON(person);
    }

JSONArray

---

相互转化关系图

• JavaBean

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

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

• JSONStr

[{"name":"xiaohua","age":18},{"name":"xiaoming","age":20}]

• JSONArray

[
    {
        "name": "xiaohua",
        "age": 18
    },
    {
        "name": "xiaoming",
        "age": 20
    }
]

Demo

1. JSONArray转JSONStr

public void test() {
        JSONObject object1 = new JSONObject();
        object1.put("age", 20);
        object1.put("name", "xiaoming");
        JSONObject object2 = new JSONObject();
        object2.put("age", 18);
        object2.put("name", "xiaohua");
        JSONArray array = new JSONArray();
        array.add(object1);
        array.add(object2);
        String str = JSON.toJSONString(array);
    }

2. JSONStr转JSONArray

public void test() {
        String str = "[{\"name\":\"xiaoming\",\"age\":20},{\"name\":\"xiaohua\",\"age\":18}]";
        JSONArray array = JSON.parseArray(str);
    }

3. JSONStr转JavaBean-List

public void test() { 
        String str = "[{\"name\":\"xiaoming\",\"age\":20},{\"name\":\"xiaohua\",\"age\":18}]";
        List<Person> personList = JSON.parseArray(str, Person.class);
    }

4. JavaBean-List转JSONStr

public void test() {
        Person person1 = new Person(18, "xiaohua");
        Person person2 = new Person(20, "xiaoming");
        List<Person> personList = new ArrayList<>();
        personList.add(person1);
        personList.add(person2);
        String str = JSON.toJSONString(personList);
    }

5. JavaBean-List转JSONArray

public void test() {
        Person person1 = new Person(18, "xiaohua");
        Person person2 = new Person(20, "xiaoming");
        List<Person> personList = new ArrayList<>();
        personList.add(person1);
        personList.add(person2);
        JSONArray array = (JSONArray) JSON.toJSON(personList);
    }