JSON在服务器端的使用

Test

package atsyc.test;

import atsyc.pojo.Dog;
import atsyc.pojo.Person;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.junit.Test;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class TestJson {
    @Test
    public void testWriteJson() throws JsonProcessingException {
        //实例化Person对象，将Person对象转换为JSON串
        Dog dog = new Dog("多多");
        Person person = new Person("茶茶",20,dog);

        //将Person对象转换成一个字符串 Jackson
        ObjectMapper objectMapper = new ObjectMapper();
        String personstr = objectMapper.writeValueAsString(person);
        System.out.println(personstr);
    }

    @Test
    public void testReadJson() throws JsonProcessingException {
        String personstr = "{\"name\":\"茶茶\",\"age\":20,\"dog\":{\"name\":\"多多\"}}";
        ObjectMapper objectMapper= new ObjectMapper();
        Person person = objectMapper.readValue(personstr,Person.class);
        System.out.println(person);
    }

    //map集合和JSON串转换
    @Test
    public void testMapJson() throws JsonProcessingException {
        Map data = new HashMap<>();
        data.put("a","valuea");
        data.put("b","valueb");
        ObjectMapper objectMapper = new ObjectMapper();
        String s = objectMapper.writeValueAsString(data);
        System.out.println(s);
    }

    //list array转换问题
    @Test
    public void tesListJson() throws JsonProcessingException {
//        List data = new ArrayList();
//        data.add("a");
//        data.add("b");
//        data.add("c");
//        String[] data = {"a","b","c"};
        Dog dog = new Dog("多多");
        Person person = new Person("茶茶",20,dog);
        List data = new ArrayList();
        data.add(person);

        ObjectMapper objectMapper = new ObjectMapper();
        String s = objectMapper.writeValueAsString(data);
        System.out.println(s);
    }

}

Dog类

package atsyc.pojo;

public class Dog {
    private String name;

    public Dog(){

    }

    public Dog(String name){
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

Person类

package atsyc.pojo;

import java.util.Objects;

public class Person {
    private String name;
    private Integer age;
    private Dog dog;

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Person person = (Person) o;
        return Objects.equals(name, person.name)&&Objects.equals(age, person.age)&&Objects.equals(dog, person.dog);
    }
    @Override
    public int hashCode() {
        return Objects.hash(name,age,dog);
    }

    public Person() {
    }

    public Person(String name, Integer age, Dog dog) {
        this.name = name;
        this.age = age;
        this.dog = dog;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public Dog getDog() {
        return dog;
    }

    public void setDog(Dog dog) {
        this.dog = dog;
    }
}