java处理Json大字符串和常用数据结构的相互转换

用到的类库：

    com.alibaba
    fastjson
    1.2.29

函数：

JSON.toJSONString，JSONObject.parseObject，JSONObject.parseArray
注意点：json转换成bean的情况，bean一定要有无参构造函数。

 

例子：

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

    public Person() {
    }

    public Person(String name, int age) {
        this.name = name;
        this.age = 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;
    }

    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.huhuhu.utils.MapUtils;
import org.junit.Test;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/**
 * Created by huorong on 17/12/20.
 */
public class JsonBeanTest {
    // map -> json
    @Test
    public void mapToJson() {
        Map map = generatorMap();
        String json = JSON.toJSONString(map);
        System.out.println(json);
    }

    // json -> map
    @Test
    public void jsonToMap() {
        String json = JSON.toJSONString(generatorMap());
        Map map = JSONObject.parseObject(json);
        System.out.println(MapUtils.getStr(map, "name"));
    }

    // bean -> json
    @Test
    public void beanToJson() {
        Person person = generatorBean();
        String json = JSON.toJSONString(person);
        System.out.println(json);
    }

    // json -> bean
    @Test
    public void jsonToBean() {
        String json = JSON.toJSONString(generatorBean());
        Person p = JSONObject.parseObject(json, Person.class);
        System.out.println(p.getAge());
    }

    // List