Android Gson深入分析

目前解析json有三种工具：org.json（Java常用的解析），fastjson（阿里巴巴工程师开发的），Gson（Google官网出的），解析速度最快的是Gson，下载地址：https://code.google.com/p/google-gson/

什么是JSON:

JSON即JavaScriptObject Natation, 它是一种轻量级的数据交换格式, 与XML一样, 是广泛被采用的客户端和服务端交互的解决方案.

JSON对象:

JSON中对象(Object)以"{"开始, 以"}"结束. 对象中的每一个item都是一个key-value对, 表现为"key:value"的形式, key-value对之间使用逗号分隔. 如:{"name":"coolxing", "age"=24, "male":true, "address":{"street":"huiLongGuan", "city":"beijing", "country":"china"}}. JSON对象的key只能是string类型的, 而value可以是string, number, false, true, null, Object对象甚至是array数组, 也就是说可以存在嵌套的情况.

JSON数组:

JSON数组(array)以"["开始, 以"]"结束, 数组中的每一个元素可以是string, number, false, true, null, Object对象甚至是array数组, 数组间的元素使用逗号分隔. 如["coolxing", 24,{"street":"huiLongGuan", "city":"beijing", "country":"china"}].

Gson的基本使用方法：

通过获取JsonReader对象解析JSON数据：

String jsonData = "[{\"username\":\"arthinking\",\"userId\":001},{\"username\":\"Jason\",\"userId\":002}]";try{JsonReader reader = new JsonReader(new StringReader(jsonData));reader.beginArray();while(reader.hasNext()){reader.beginObject();while(reader.hasNext()){String tagName = reader.nextName();if(tagName.equals("username")){System.out.println(reader.nextString());}else if(tagName.equals("userId")){System.out.println(reader.nextString());}}reader.endObject();}reader.endArray();}catch(Exception e){e.printStackTrace();}

通过把JSON数据映射成一个对象，使用Gson对象的fromJson()方法获取一个对象数组进行操作：

创建JSON数据对应的一个POJO对象User.java：

public class User {private String username ;private int userId ;public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}public int getUserId() {return userId;}public void setUserId(int userId) {this.userId = userId;}}

使用Gson对象获取User对象数据进行相应的操作：

Type listType = new TypeToken<LinkedList<User>>(){}.getType();Gson gson = new Gson();LinkedList<User> users = gson.fromJson(jsonData, listType);for (Iterator iterator = users.iterator(); iterator.hasNext();) {User user = (User) iterator.next();System.out.println(user.getUsername());System.out.println(user.getUserId());}

如果要处理的JSON字符串只包含一个JSON对象，则可以直接使用fromJson获取一个User对象：

String jsonData = "{\"username\":\"arthinking\",\"userId\":001}";Gson gson = new Gson();User user = gson.fromJson(jsonData, User.class);System.out.println(user.getUsername());System.out.println(user.getUserId());

解析复杂实例：

数据格式：

[java] view plain copy print ?

{
"data":{
"partnerteamlist":[
{
"pteamId":72825,
"ptitle":"随摄影/共6套服装/准爸准妈共拍/免费肚画/底片全送。",
"pteamprice":288
},
{
"pteamId":72598,
"ptitle":"随摄影/拍摄200张/4本相册/品质拍摄/送全新婚纱。",
"pteamprice":2888
},
{
"pteamId":72613,
"ptitle":"随摄影/送全新婚纱/多外景拍摄/服装不限数量/绝无二次消费！",
"pteamprice":3699
},
{
"pteamId":72638,
"ptitle":"随摄影/服装不限数量/高品质拍摄260张/送全新婚纱。",
"pteamprice":4299
},
{
"pteamId":72716,
"ptitle":"随摄影/3组服装造型/内外景拍摄/完全透明消费！",
"pteamprice":388
}
],
"liketeamlist":[
{
"lteamId":65886,
"ltitle":"爱丽尔婚纱摄影/2本相册/6套服装造型/拍摄不限最低拍摄150张。",
"limage":"http://img.pztuan.com/upfile/team/2013/0712/201307120257551465.jpg",
"lteamprice":518,
"lmarketprice":3999
},
{
"lteamId":57133,
"ltitle":"陶冶摄影/婚纱闺蜜/6组服装造型/拍摄不低于120张！",
"limage":"http://img.pztuan.com/upfile/team/2013/0628/201306281115249737.jpg",
"lteamprice":580,
"lmarketprice":3380
}
],
"feedbacks":{
"feedbacklist":[
{
"comment":"5分",
"createtime":"2014.07.0813:38",
"score":5,
"username":"l***2"
}
],
"totalcount":1,
"totalscore":5
}
},
"err":null,
"state":1
}

实体类（里面的成员变量和接口的返回值名称一一对应才能保证解析正确）：

[java] view plain copy print ?

packagecom.pztuan.entity;
importjava.util.List;
publicclassOtherDetail{
privateintstate;
privateList<err>err;
privateOtherDetail2data;
publicintgetState(){
returnstate;
}
publicvoidsetState(intstate){
this.state=state;
}
publicList<err>getErr(){
returnerr;
}
publicvoidsetErr(List<err>err){
this.err=err;
}
publicOtherDetail2getData(){
returndata;
}
publicvoidsetData(OtherDetail2data){
this.data=data;
}
publicclassOtherDetail2{
privateList<partnerteamlist>partnerteamlist;
privateList<liketeamlist>liketeamlist;
privateList<feedbacks>feedbacks;
publicList<liketeamlist>getLiketeamlist(){
returnliketeamlist;
}
publicvoidsetLiketeamlist(List<liketeamlist>liketeamlist){
this.liketeamlist=liketeamlist;
}
publicList<feedbacks>getFeedbacks(){
returnfeedbacks;
}
publicvoidsetFeedbacks(List<feedbacks>feedbacks){
this.feedbacks=feedbacks;
}
publicclasspartnerteamlist{
privateintpteamId;
privateStringptitle;
privateDoublepteamprice;
publicintgetPteamId(){
returnpteamId;
}
publicvoidsetPteamId(intpteamId){
this.pteamId=pteamId;
}
publicStringgetPtitle(){
returnptitle;
}
publicvoidsetPtitle(Stringptitle){
this.ptitle=ptitle;
}
publicDoublegetPteamprice(){
returnpteamprice;
}
publicvoidsetPteamprice(Doublepteamprice){
this.pteamprice=pteamprice;
}
}
publicclassliketeamlist{
privateintlteamId;
privateStringltitle;
privateStringlimage;
privateDoublelteamprice;
privateDoublelmarketprice;
publicintgetLteamId(){
returnlteamId;
}
publicvoidsetLteamId(intlteamId){
this.lteamId=lteamId;
}
publicStringgetLtitle(){
returnltitle;
}
publicvoidsetLtitle(Stringltitle){
this.ltitle=ltitle;
}
publicStringgetLimage(){
returnlimage;
}
publicvoidsetLimage(Stringlimage){
this.limage=limage;
}
publicDoublegetLteamprice(){
returnlteamprice;
}
publicvoidsetLteamprice(Doublelteamprice){
this.lteamprice=lteamprice;
}
publicDoublegetLmarketprice(){
returnlmarketprice;
}
publicvoidsetLmarketprice(Doublelmarketprice){
this.lmarketprice=lmarketprice;
}
}
publicclassfeedbacks{
privateinttotalcount;
privateDoubletotalscore;
privateList<feedbacklist>feedbacklist;
publicintgetTotalcount(){
returntotalcount;
}
publicvoidsetTotalcount(inttotalcount){
this.totalcount=totalcount;
}
publicDoublegetTotalscore(){
returntotalscore;
}
publicvoidsetTotalscore(Doubletotalscore){
this.totalscore=totalscore;
}
publicList<feedbacklist>getFeedbacklist(){
returnfeedbacklist;
}
publicvoidsetFeedbacklist(List<feedbacklist>feedbacklist){
this.feedbacklist=feedbacklist;
}
publicclassfeedbacklist{
privateStringusername;
privateStringcomment;
privateStringcreatetime;
privateDoublescore;
publicStringgetUsername(){
returnusername;
}
publicvoidsetUsername(Stringusername){
this.username=username;
}
publicStringgetComment(){
returncomment;
}
publicvoidsetComment(Stringcomment){
this.comment=comment;
}
publicStringgetCreatetime(){
returncreatetime;
}
publicvoidsetCreatetime(Stringcreatetime){
this.createtime=createtime;
}
publicDoublegetScore(){
returnscore;
}
publicvoidsetScore(Doublescore){
this.score=score;
}
}
}
publicList<partnerteamlist>getPartnerteamlist(){
returnpartnerteamlist;
}
publicvoidsetPartnerteamlist(List<partnerteamlist>partnerteamlist){
this.partnerteamlist=partnerteamlist;
}
}
publicclasserr{
privateintcode;
privateStringmsg;
publicintgetCode(){
returncode;
}
publicvoidsetCode(intcode){
this.code=code;
}
publicStringgetMsg(){
returnmsg;
}
publicvoidsetMsg(Stringmsg){
this.msg=msg;
}
}
}

注意上面内部类的运用。

解析：

[java] view plain copy print ?

Gsongson=newGson();
OtherDetaild=gson.fromJson(jsonString,Detail.class);//取值的时候就从父类一层一层调子类成员（重要）

Android(安卓)Gson深入分析

Android Gson深入分析

更多相关文章

随机推荐