json数据转java对象(复杂java对象)

直接贴代码:

主要代码:

package json;

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

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

/**
 * 要想实现JSON和java对象之间的互转，需要借助第三方jar包，这里使用json-lib这个jar包，
 * json-lib需要commons-beanutils、commons-collections、commons-lang、
 * commons-logging、ezmorph五个包的支持.
 * json-lib提供了几个类可以完成此功能，例，JSONObject、JSONArray。
 * 从类的名字上可以看出JSONObject转化的应该是对象格式的，而JSONArray转化的则应该是数组对象（即，带[]形式）的。
 * @author hg
 *
 */
@SuppressWarnings("rawtypes")
public class JsonHandle {

    public static void main(String[] args) {
        JsonHandle jsonHandle = new JsonHandle();
        jsonHandle.JsonArrayDemo();
        jsonHandle.JsonObjectDemo();
    }


    /**
     * JSON 数组对象格式 [ 开始的json数据
     */
    public void JsonArrayDemo(){

        String jsonStr = "[{\"name\":\"小贺\",\"age\":20,\"sex\":\"男\","
                + "\"pictures\":[{\"fileName\":\"1.jpg\",\"pictureUrl\":\"http://www.1.jsp\"},"
                + "{\"fileName\":\"2.jpg\",\"pictureUrl\":\"http://www.2.jsp\"}]},"
                + "{\"name\":\"小露\",\"age\":19,\"sex\":\"女\","
                + "\"pictures\":[{\"fileName\":\"3.jpg\",\"pictureUrl\":\"http://www.3.jsp\"},"
                + "{\"fileName\":\"4.jpg\",\"pictureUrl\":\"http://www.4.jsp\"}]}]";

        //数组对象格式使用JSONArray
        JSONArray jsonArray = JSONArray.fromObject(jsonStr);

        //对应json的数组 List<PersonalInfo>
        List<PersonalInfo> personalInfos =new ArrayList<PersonalInfo>();        

        //遍历 jsonArray
        for(int i=;i<jsonArray.size();i++){

            //获得jsonArray的第 i 个元素
            Object o = jsonArray.get(i);

            //转换为单个 JSONObject 对象
            JSONObject jsonObject = JSONObject.fromObject(o);

            /*
             * 当其中属性有类似List, Map,ArrayList就不可以了。 会报错：MorphDynaBean cannot be  
             * cast to ******。
             * 在JSONObject.toBean的时候如果转换的类中有集合，
             * 可以先定义    Map<String, Class<E>> classMap = new HashMap<String, Class<E>>();
             * 在classMap中put你要转换的类中的集合名，比如:classMap.put("pictures", Picture.class);
             * 然后在toBean()的时候把参数加上，
             * 例如：PersonalInfo personalInfo = 
             * (PersonalInfo)JSONObject.toBean(jsonObject, PersonalInfo.class,classMap);
             */
            Map<String, Class> pictureMap = new HashMap<String, Class>();

            pictureMap.put("pictures",Picture.class);

            //转化为java对象
            PersonalInfo personalInfo = 
                    (PersonalInfo)JSONObject.toBean(jsonObject, PersonalInfo.class,pictureMap);

            //添加对象至数组
            personalInfos.add(personalInfo);
        }

        for(PersonalInfo pi : personalInfos){
            //对象toString()打印:PersonalInfo {name=小贺, age=20, sex=男, pictures=
            //[{fileName=1.jpg, pictureUrl=http://www.1.jsp},
            //{fileName=2.jpg, pictureUrl=http://www.2.jsp}]}
            System.out.println(pi.toString());
        }
    }

    /**
     * JSON的对象格式的字符串  { 开始的json数据
     */
    public void JsonObjectDemo(){

        String jsonStr = "{\"name\":\"小贺\",\"age\":20,\"sex\":\"男\","
                + "\"pictures\":[{\"fileName\":\"1.jpg\",\"pictureUrl\":\"http://www.1.jsp\"},"
                + "{\"fileName\":\"2.jpg\",\"pictureUrl\":\"http://www.2.jsp\"}]}";

        //1、使用JSONObject
        JSONObject jsonObject=JSONObject.fromObject(jsonStr);

        Map<String, Class> pictureMap = new HashMap<String, Class>();

        pictureMap.put("pictures",Picture.class);

        //转化为java对象
        PersonalInfo personalInfo = 
                (PersonalInfo)JSONObject.toBean(jsonObject, PersonalInfo.class,pictureMap);

        //对象toString()打印:PersonalInfo {name=小贺, age=20, sex=男, 
        //pictures=[{fileName=1.jpg, pictureUrl=http://www.1.jsp},
        //{fileName=2.jpg, pictureUrl=http://www.2.jsp}]}
        System.out.println(personalInfo.toString());

    }
}
           

PersonalInfo 实体类 :

package json;

import java.util.List;

/**
 * 个人信息
 * @author hg
 *
 */
public class PersonalInfo {
    private String name;            //姓名
    private Integer age;            //年龄
    private String sex;             //性别
    private List<Picture> pictures; //照片

    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 String getSex() {
        return sex;
    }
    public void setSex(String sex) {
        this.sex = sex;
    }
    public List<Picture> getPictures() {
        return pictures;
    }
    public void setPictures(List<Picture> pictures) {
        this.pictures = pictures;
    }

    public String toString() {
        String picturesStr = "";
        for(int i=;i<pictures.size();i++){
            picturesStr+=pictures.get(i).toString();
            if(i<pictures.size()-){
                picturesStr+=",";
            }
        }
        return "PersonalInfo {name=" + name + ", age=" 
        + age + ", sex=" + sex + ", pictures=[" + picturesStr+ "]}";
    }
}
           

Picture 实体类

package json;

/**
 * 个人照片Entity
 * @author hg
 *
 */
public class Picture {
    private String fileName;    //文件名
    private String pictureUrl;  //照片Url

    public String getFileName() {
        return fileName;
    }
    public void setFileName(String fileName) {
        this.fileName = fileName;
    }
    public String getPictureUrl() {
        return pictureUrl;
    }
    public void setPictureUrl(String pictureUrl) {
        this.pictureUrl = pictureUrl;
    }

    public String toString() {
        return "{fileName=" + fileName + ", pictureUrl=" + pictureUrl + "}";
    }
}
           

对象型json数据

{
    "name":"小贺",
    "age":,
    "sex":"男",
    "pictures":[
        {
            "fileName":"1.jpg",
            "pictureUrl":"http://www.1.jsp"
        },
        {
            "fileName":"2.jpg",
            "pictureUrl":"http://www.2.jsp"
        }
    ]
}
           

数组型json数据

[
    {
        "name":"小贺",
        "age":,
        "sex":"男",
        "pictures":[
            {
                "fileName":"1.jpg",
                "pictureUrl":"http://www.1.jsp"
            },
            {
                "fileName":"2.jpg",
                "pictureUrl":"http://www.2.jsp"
            }
        ]
    },
    {
        "name":"小露",
        "age":,
        "sex":"女",
        "pictures":[
            {
                "fileName":"3.jpg",
                "pictureUrl":"http://www.3.jsp"
            },
            {
                "fileName":"4.jpg",
                "pictureUrl":"http://www.4.jsp"
            }
        ]
    }
]