首先是Gson的使用

public class GsonUse {    PRivate static Gson gson = new Gson();    /**     *      * @param args     */    public static void main(String[] args) {        f1();    }    private static  void f1(){        StandardData standardData = new StandardData();        standardData.setCode("A20000");        standardData.setData(222);        //將對(duì)象轉(zhuǎn)換為Json格式數(shù)據(jù)        String jsons = gson.toJson(standardData);        System.out.println(jsons);//{"code":"A20000","data":222}        //根據(jù)屬性解析json數(shù)據(jù)        JsonParser jsonParser = new JsonParser();        JsonElement jsonElement = jsonParser.parse(jsons);        JsonObject jsonObject = jsonElement.getAsJsonObject();        int data =  jsonObject.get("data").getAsInt();        System.out.println(data);//222        //直接將Json轉(zhuǎn)化為對(duì)象        StandardData standardData1 = gson.fromJson(jsons,StandardData.class);        System.out.println(standardData1);//StandardData [code=A20000, data=222]        //將json格式數(shù)據(jù)按照一定的模型解析出來(lái)        Map<String,Integer> map = Maps.newHashMap();        map.put("1",2);        String mapJson = gson.toJson(map);        HashMap<String, Integer> mapUrl = gson.fromJson(mapJson,                new TypeToken<HashMap<String, Integer>>() {                }.getType());        System.out.println(map);//{1=2}    }}class StandardData {    private String code;    private Integer data;    public StandardData() {    }    public Integer getData() {        return data;    }    public void setData(Integer data) {        this.data = data;    }    public String getCode() {        return code;    }    public void setCode(String code) {        this.code = code;    }    @Override    public String toString() {        return "StandardData [code=" + code + ", data=" + data + "]";    }}
alibaba JSON的使用
package com.erdong.learn.util.alibaba.json;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;import com.alibaba.fastjson.JSON;import com.alibaba.fastjson.JSONArray;import com.alibaba.fastjson.JSONObject;  //下面是FastJson的簡(jiǎn)介：常用的方法！  //  Fastjson API入口類是com.alibaba.fastjson.JSON，常用的序列化操作都可以在JSON類上的靜態(tài)方法直接完成。  //  public static final Object parse(String text); // 把JSON文本parse為JSONObject或者JSONArray   //  public static final JSONObject parSEObject(String text)； // 把JSON文本parse成JSONObject      //  public static final <T> T parseObject(String text, Class<T> clazz); // 把JSON文本parse為JavaBean   //  public static final JSONArray parseArray(String text); // 把JSON文本parse成JSONArray   //  public static final <T> List<T> parseArray(String text, Class<T> clazz); //把JSON文本parse成JavaBean集合   //  public static final String toJSONString(Object object); // 將JavaBean序列化為JSON文本   //  public static final String toJSONString(Object object, boolean prettyFormat); // 將JavaBean序列化為帶格式的JSON文本   //  public static final Object toJSON(Object javaObject); 將JavaBean轉(zhuǎn)換為JSONObject或者JSONArray（和上面方法的區(qū)別是返回值是不一樣的）    public class JsonDemo {        public static void main(String[] args) {                    json2JsonObjectM1();//將Json文本數(shù)據(jù)信息轉(zhuǎn)換為JsonObject對(duì)象，然后利用鍵值對(duì)的方式獲取信息          json2BeanM2();//將Json文本數(shù)據(jù)轉(zhuǎn)換為JavaBean數(shù)據(jù)！          json2JSONArrayM3();//將json數(shù)據(jù)轉(zhuǎn)化為JSONArray:           json2JavaBeanM4();//將JSON文本轉(zhuǎn)換為JavaBean的集合；轉(zhuǎn)換為單純的1個(gè)Object：parseObject(String text, Class<T> clazz);           bean2JsonM5();//將JavaBean轉(zhuǎn)換為Json格式的數(shù)據(jù)/Json文本 用戶數(shù)據(jù)的傳遞：例如上傳服務(wù)器          bean2JSONObjectM6();//將JavaBean轉(zhuǎn)換為JSON對(duì)象          complexExampleM7();//一個(gè)相對(duì)復(fù)雜的例子：          complex2JsonM8();//一個(gè)復(fù)雜的Object到Json的Demo          complexMap2JsonM9();//將Map數(shù)據(jù)轉(zhuǎn)換為JsonString的Demo；這個(gè)對(duì)RedBoy服務(wù)端不就直接破了嘛！      }        /**      * 將Json文本數(shù)據(jù)信息轉(zhuǎn)換為JsonObject對(duì)象，然后利用鍵值對(duì)的方式獲取信息      */      private static void json2JsonObjectM1() {          //一個(gè)JsonObject文本數(shù)據(jù)          String s = "{/"name/":/"pig/"}";        //將JsonObject數(shù)據(jù)轉(zhuǎn)換為Json          JSONObject object = JSON.parseObject(s);          //利用鍵值對(duì)的方式獲取到值          System.out.println(object.get("name"));  //pig             }            /**      * 將Json文本數(shù)據(jù)轉(zhuǎn)換為JavaBean數(shù)據(jù)！      * 需要注意的是：這時(shí)候的Json文本信息中的鍵的名稱必須和JavaBean中的字段名稱一樣！鍵中沒(méi)有的在這個(gè)JavaBean中就顯示為null！      */      private static void json2BeanM2() {          String s = "{/"id/":/"0375/",/"city/":/"平頂山/"}";          //一個(gè)簡(jiǎn)單方便 的方法將Json文本信息轉(zhuǎn)換為JsonObject對(duì)象的同時(shí)轉(zhuǎn)換為JavaBean對(duì)象！          Weibo weibo = JSON.parseObject(s, Weibo.class);//Weibo類在下邊定義          System.out.println(weibo.getId());          System.out.println(weibo.getCity());          //0375        //平頂山    }          /**      * 將Map類型的數(shù)據(jù)轉(zhuǎn)換為JsonString      */      private static void complexMap2JsonM9() {          Group group = new Group();          group.setId(1);          group.setName("group");                    User user1 = new User();          user1.setId(2);          user1.setName("user1");            User user2 = new User();          user2.setId(3);          user2.setName("user2");          group.getList().add(user1);          group.getList().add(user2);                    Map<Integer, Object> map = new HashMap<Integer,Object>();          map.put(1, "No.1");          map.put(2, "No.2");          map.put(3, group.getList());                    String jsonString = JSON.toJSONString(map);          System.out.println(jsonString);          /**          *  輸出：{1:"No.1",2:"No.2",3:[{"id":2,"name":"user1"},{"id":3,"name":"user2"}]}          */      }        /**      * 由一個(gè)復(fù)雜的Object到Json的Demo      */      private static void complex2JsonM8() {          Group group = new Group();          group.setId(1);          group.setName("group");                    User user1 = new User();          user1.setId(2);          user1.setName("user1");            User user2 = new User();          user2.setId(3);          user2.setName("user2");          group.getList().add(user1);          group.getList().add(user2);          String jsonString = JSON.toJSONString(group);          System.out.println(jsonString);          /**          *  輸出：{"id":1,"list":[{"id":2,"name":"user1"},{"id":3,"name":"user2"}],"name":"group"}          */      }        /**      * 一個(gè)相對(duì)復(fù)雜的例子：      * JSON文本數(shù)據(jù)：      *      首先是JSONObject，轉(zhuǎn)換為JSONArray；      *      然后將JSONArray轉(zhuǎn)換為JavaBean      */      private static void complexExampleM7() {          String s = "{js:[{id:/"110000/",/"city/":/"北#001京市/"},{id:/"110000/",/"city/":/"北#002京市/"}"                  + ",{id:/"110000/",/"city/":/"北#002京市/"},{id:/"110000/",/"city/":/"北#002京市/"},"                  + "{id:/"110000/",/"city/":/"#006北#005京市/"},"                  + "{id:/"110000/",/"city/":/"北#002京市/"},"                  + "{id:/"110000/",/"city/":/"北#002京市/"},{id:/"120000/",/"city/":/"天#009津市/"}]}";                    JSONObject object = JSON.parseObject(s);          Object jsonArray = object.get("js");          System.out.println(jsonArray);          List<Weibo> list = JSON.parseArray(jsonArray+"", Weibo.class);          for (Weibo weibo : list) {              System.out.println(weibo.getCity());          }      }        /**      * 將JavaBean轉(zhuǎn)換為JSON對(duì)象      */      private static void bean2JSONObjectM6() {          Weibo weibo = new Weibo("0373", "洛陽(yáng)");          JSONObject json = (JSONObject) JSON.toJSON(weibo);          System.out.println(json.get("id"));  //0373    }        /**      * 將JSON文本轉(zhuǎn)換為JavaBean的集合；      * 內(nèi)部實(shí)現(xiàn)肯定是：首先轉(zhuǎn)換為JSONArray，然后再轉(zhuǎn)換為L(zhǎng)ist集合      */      private static void json2JavaBeanM4() {          String s = "[{/"id/":/"0375/",/"city/":/"平頂山/"},{/"id/":/"0377/",/"city/":/"南陽(yáng)/"}]";          List<Weibo> list = JSON.parseArray(s, Weibo.class);          for (Weibo weibo : list) {              System.out.println(weibo.getCity());            //平頂山 南陽(yáng)        }      }        /**      * 將json數(shù)據(jù)轉(zhuǎn)化為JSONArray:      * 注意：獲取到JSONArray之后（我們這里只是獲取到JSONArray而不是JavaBean的List集合）      * 獲取JSONArray中的數(shù)據(jù)轉(zhuǎn)換為String類型需要在外邊加"";      */      private static void json2JSONArrayM3() {          String s = "[{/"id/":/"0375/",/"city/":/"平頂山/"},{/"id/":/"0377/",/"city/":/"南陽(yáng)/"}]";          //將JSON文本轉(zhuǎn)換為JSONArray          JSONArray array = JSON.parseArray(s);          //這行必須寫：必須加上+"";不然會(huì)報(bào)出類型強(qiáng)轉(zhuǎn)異常！          String str = array.get(1)+"";          System.out.println(array.get(0));          JSONObject object = JSON.parseObject(str);          System.out.println(object.get("id"));         //{"city":"平頂山","id":"0375"}         // 0377    }          /**      * 將JavaBean轉(zhuǎn)換為Json格式的數(shù)據(jù)/Json文本      * 用戶數(shù)據(jù)的傳遞：例如上傳服務(wù)器      */      private static void bean2JsonM5() {          Weibo weibo = new Weibo("123456", "上海");          String string = JSON.toJSONString(weibo);          System.out.println(string);          //{"city":"上海","id":"123456"}    }}class Group{    private int id;    private String name;    private List<User> list = new ArrayList<User>();    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public List<User> getList() {        return list;    }    public void setList(List<User> list) {        this.list = list;    }}class User{    private int id;    private String name;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }}class Weibo {    private String id;    private String city;    public Weibo(String id, String city) {        this.id = id;        this.city = city;    }    public Weibo() {    }    public String getId() {        return id;    }    public void setId(String id) {        this.id = id;    }    public String getCity() {        return city;    }    public void setCity(String city) {        this.city = city;    }}最后聲明，本文中Gson的使用是自己原創(chuàng)而JSON的使用是從網(wǎng)上摘錄而來(lái)。