• Android Gson解析


    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JavaScript Object 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:

    1. {  
    2.     "data": {  
    3.         "partnerteamlist": [  
    4.             {  
    5.                 "pteamId": 72825,  
    6.                 "ptitle": "随摄影/共6套服装/准爸准妈共拍/免费肚画/底片全送。",  
    7.                 "pteamprice": 288  
    8.             },  
    9.             {  
    10.                 "pteamId": 72598,  
    11.                 "ptitle": "随摄影/拍摄200张/4本相册/品质拍摄/送全新婚纱。",  
    12.                 "pteamprice": 2888  
    13.             },  
    14.             {  
    15.                 "pteamId": 72613,  
    16.                 "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!",  
    17.                 "pteamprice": 3699  
    18.             },  
    19.             {  
    20.                 "pteamId": 72638,  
    21.                 "ptitle": "随摄影/服装不限数量/高品质拍摄260张/送全新婚纱。",  
    22.                 "pteamprice": 4299  
    23.             },  
    24.             {  
    25.                 "pteamId": 72716,  
    26.                 "ptitle": "随摄影/3组服装造型/内外景拍摄/完全透明消费!",  
    27.                 "pteamprice": 388  
    28.             }  
    29.         ],  
    30.         "liketeamlist": [  
    31.             {  
    32.                 "lteamId": 65886,  
    33.                 "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。",  
    34.                 "limage": "http://img.pztuan.com/upfile/team/2013/0712/201307120257551465.jpg",  
    35.                 "lteamprice": 518,  
    36.                 "lmarketprice": 3999  
    37.             },  
    38.             {  
    39.                 "lteamId": 57133,  
    40.                 "ltitle": "陶冶摄影/婚纱闺蜜/6组服装造型/拍摄不低于120张!",  
    41.                 "limage": "http://img.pztuan.com/upfile/team/2013/0628/201306281115249737.jpg",  
    42.                 "lteamprice": 580,  
    43.                 "lmarketprice": 3380  
    44.             }  
    45.         ],  
    46.         "feedbacks": {  
    47.             "feedbacklist": [  
    48.                 {  
    49.                     "comment": "5分",  
    50.                     "createtime": "2014.07.08 13:38",  
    51.                     "score": 5,  
    52.                     "username": "l***2"  
    53.                 }  
    54.             ],  
    55.             "totalcount": 1,  
    56.             "totalscore": 5  
    57.         }  
    58.     },  
    59.     "err": null,  
    60.     "state": 1  
    61. }  


    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):

    1. package com.pztuan.entity;  
    2.   
    3. import java.util.List;  
    4.   
    5. public class OtherDetail {  
    6.   
    7.     private int state;  
    8.     private List<err> err;  
    9.     private OtherDetail2 data;  
    10.   
    11.     public int getState() {  
    12.         return state;  
    13.     }  
    14.   
    15.     public void setState(int state) {  
    16.         this.state = state;  
    17.     }  
    18.   
    19.     public List<err> getErr() {  
    20.         return err;  
    21.     }  
    22.   
    23.     public void setErr(List<err> err) {  
    24.         this.err = err;  
    25.     }  
    26.   
    27.     public OtherDetail2 getData() {  
    28.         return data;  
    29.     }  
    30.   
    31.     public void setData(OtherDetail2 data) {  
    32.         this.data = data;  
    33.     }  
    34.   
    35.     public class OtherDetail2 {  
    36.         private List<partnerteamlist> partnerteamlist;  
    37.         private List<liketeamlist> liketeamlist;  
    38.         private List<feedbacks> feedbacks;  
    39.   
    40.         public List<liketeamlist> getLiketeamlist() {  
    41.             return liketeamlist;  
    42.         }  
    43.   
    44.         public void setLiketeamlist(List<liketeamlist> liketeamlist) {  
    45.             this.liketeamlist = liketeamlist;  
    46.         }  
    47.   
    48.         public List<feedbacks> getFeedbacks() {  
    49.             return feedbacks;  
    50.         }  
    51.   
    52.         public void setFeedbacks(List<feedbacks> feedbacks) {  
    53.             this.feedbacks = feedbacks;  
    54.         }  
    55.   
    56.         public class partnerteamlist {  
    57.             private int pteamId;  
    58.             private String ptitle;  
    59.             private Double pteamprice;  
    60.   
    61.             public int getPteamId() {  
    62.                 return pteamId;  
    63.             }  
    64.   
    65.             public void setPteamId(int pteamId) {  
    66.                 this.pteamId = pteamId;  
    67.             }  
    68.   
    69.             public String getPtitle() {  
    70.                 return ptitle;  
    71.             }  
    72.   
    73.             public void setPtitle(String ptitle) {  
    74.                 this.ptitle = ptitle;  
    75.             }  
    76.   
    77.             public Double getPteamprice() {  
    78.                 return pteamprice;  
    79.             }  
    80.   
    81.             public void setPteamprice(Double pteamprice) {  
    82.                 this.pteamprice = pteamprice;  
    83.             }  
    84.   
    85.         }  
    86.   
    87.         public class liketeamlist {  
    88.             private int lteamId;  
    89.             private String ltitle;  
    90.             private String limage;  
    91.             private Double lteamprice;  
    92.             private Double lmarketprice;  
    93.   
    94.             public int getLteamId() {  
    95.                 return lteamId;  
    96.             }  
    97.   
    98.             public void setLteamId(int lteamId) {  
    99.                 this.lteamId = lteamId;  
    100.             }  
    101.   
    102.             public String getLtitle() {  
    103.                 return ltitle;  
    104.             }  
    105.   
    106.             public void setLtitle(String ltitle) {  
    107.                 this.ltitle = ltitle;  
    108.             }  
    109.   
    110.             public String getLimage() {  
    111.                 return limage;  
    112.             }  
    113.   
    114.             public void setLimage(String limage) {  
    115.                 this.limage = limage;  
    116.             }  
    117.   
    118.             public Double getLteamprice() {  
    119.                 return lteamprice;  
    120.             }  
    121.   
    122.             public void setLteamprice(Double lteamprice) {  
    123.                 this.lteamprice = lteamprice;  
    124.             }  
    125.   
    126.             public Double getLmarketprice() {  
    127.                 return lmarketprice;  
    128.             }  
    129.   
    130.             public void setLmarketprice(Double lmarketprice) {  
    131.                 this.lmarketprice = lmarketprice;  
    132.             }  
    133.         }  
    134.   
    135.         public class feedbacks {  
    136.             private int totalcount;  
    137.             private Double totalscore;  
    138.             private List<feedbacklist> feedbacklist;  
    139.   
    140.             public int getTotalcount() {  
    141.                 return totalcount;  
    142.             }  
    143.   
    144.             public void setTotalcount(int totalcount) {  
    145.                 this.totalcount = totalcount;  
    146.             }  
    147.   
    148.             public Double getTotalscore() {  
    149.                 return totalscore;  
    150.             }  
    151.   
    152.             public void setTotalscore(Double totalscore) {  
    153.                 this.totalscore = totalscore;  
    154.             }  
    155.   
    156.             public List<feedbacklist> getFeedbacklist() {  
    157.                 return feedbacklist;  
    158.             }  
    159.   
    160.             public void setFeedbacklist(List<feedbacklist> feedbacklist) {  
    161.                 this.feedbacklist = feedbacklist;  
    162.             }  
    163.   
    164.             public class feedbacklist {  
    165.                 private String username;  
    166.                 private String comment;  
    167.                 private String createtime;  
    168.                 private Double score;  
    169.   
    170.                 public String getUsername() {  
    171.                     return username;  
    172.                 }  
    173.   
    174.                 public void setUsername(String username) {  
    175.                     this.username = username;  
    176.                 }  
    177.   
    178.                 public String getComment() {  
    179.                     return comment;  
    180.                 }  
    181.   
    182.                 public void setComment(String comment) {  
    183.                     this.comment = comment;  
    184.                 }  
    185.   
    186.                 public String getCreatetime() {  
    187.                     return createtime;  
    188.                 }  
    189.   
    190.                 public void setCreatetime(String createtime) {  
    191.                     this.createtime = createtime;  
    192.                 }  
    193.   
    194.                 public Double getScore() {  
    195.                     return score;  
    196.                 }  
    197.   
    198.                 public void setScore(Double score) {  
    199.                     this.score = score;  
    200.                 }  
    201.   
    202.             }  
    203.         }  
    204.   
    205.         public List<partnerteamlist> getPartnerteamlist() {  
    206.             return partnerteamlist;  
    207.         }  
    208.   
    209.         public void setPartnerteamlist(List<partnerteamlist> partnerteamlist) {  
    210.             this.partnerteamlist = partnerteamlist;  
    211.         }  
    212.     }  
    213.   
    214.     public class err {  
    215.         private int code;  
    216.         private String msg;  
    217.   
    218.         public int getCode() {  
    219.             return code;  
    220.         }  
    221.   
    222.         public void setCode(int code) {  
    223.             this.code = code;  
    224.         }  
    225.   
    226.         public String getMsg() {  
    227.             return msg;  
    228.         }  
    229.   
    230.         public void setMsg(String msg) {  
    231.             this.msg = msg;  
    232.         }  
    233.     }  
    234. }  


    注意上面内部类的运用。

    解析:

    1. Gson gson = new Gson();  
    2. OtherDetail d = 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)  

    若出现引用异常,请查看Java内部类设计原则。

    转自:http://blog.csdn.net/rain_butterfly/article/details/38404293?utm_source=tuicool&utm_medium=referral

    参考:http://www.itzhai.com/android-to-parse-json-data-using-gson.html

               http://blog.csdn.net/caijunjun1006/article/details/11762841

  • 相关阅读:
    [NOIP2011] 玛雅游戏
    [bzoj4025] 二分图
    [10.2模拟] tree
    [10.3模拟] color
    [10.2模拟] teach
    [10.2模拟] plan
    [10.2模拟] book
    [bzoj4999] This Problem Is Too Simple!
    [9.28模拟] good
    [bzoj3884] 上帝与集合的正确用法
  • 原文地址:https://www.cnblogs.com/Talon-lly/p/5773899.html
Copyright © 2020-2023  润新知