jar包
1 <dependency>
2 <groupId>com.alibaba</groupId>
3 <artifactId>fastjson</artifactId>
4 <version>1.2.58</version>
5 </dependency>
View Code JsonObject
1 package com.baidu.com;
2
3
4
5 import java.util.Map;
6
7 import com.alibaba.fastjson.JSON;
8 import com.alibaba.fastjson.JSONArray;
9 import com.alibaba.fastjson.JSONObject;
10
11
12 public class JsonTest {
13
14 public static void main(String[] args) {
15 // TODO Auto-generated method stub
16 String jsonString = "
" +
17 "{
" +
18 " "count":20,
" +
19 " "start":0,
" +
20 " "total":641,
" +
21 " "books":[
" +
22 " {
" +
23 " "id":"4866934",
" +
24 " "title":"Python基础教程"
" +
25 " },
" +
26 " {
" +
27 " "id":"3117898",
" +
28 " "title":"Python源码剖析"
" +
29 " },
" +
30 " {
" +
31 " "id":"3948354",
" +
32 " "title":"Python学习手册"
" +
33 " },
" +
34 " {
" +
35 " "id":"3884108",
" +
36 " "title":"可爱的Python"
" +
37 " }
" +
38 " ]
" +
39 "}";
40 //串转json
41 JSONObject result01 = (JSONObject) JSON.parse(jsonString);
42 System.out.println(result01);
43
44 //获取json数组
45 System.out.println(result01.get("total"));
46 //判断json的value的数据类型
47 System.out.println(result01.get("total").toString().startsWith("641"));
48 //result01.get
49 JSONArray result02 = result01.getJSONArray("employees");
50
51 System.out.println("33");
52
53 // json数据中下一维度所有key字段获取
54 JSONObject jsonObj = JSON.parseObject(jsonString);
55 for (Map.Entry<String, Object> entry : jsonObj.entrySet()) {
56 System.out.println(entry.getKey() + ":" + entry.getValue());
57
58 }
59 }
60
61 }
View Code
JsonXpath
1 //jsonpath
2 //判断串是否是json格式 json对象 json数组
3 //String string2 = "dd";
4 String string2 = "{"total":641,"books":[{"id":"4866934","title":"Python基础教程"},{"id":"3117898","title":"Python源码剖析"},{"id":"3948354","title":"Python学习手册"},{"id":"3884108","title":"可爱的Python"}],"count":20,"start":0}
";
5 //String string2 = "[{"id":"4866934","title":"Python基础教程"},{"id":"3117898","title":"Python源码剖析"},{"id":"3948354","title":"Python学习手册"},{"id":"3884108","title":"可爱的Python"}]";
6 System.out.println(JSON.isValid(string2));
7 System.out.println(JSON.isValidObject(string2));
8 System.out.println(JSON.isValidArray(string2));
9
10 int result03 = (Integer) JSONPath.read(string2, "$.total");
11 int result031 = (Integer) JSONPath.read(string2, "total");
12 List<Integer> result0311 = (List<Integer>) JSONPath.read(string2, "books.id");
13 List<Integer> result03111 = (List<Integer>) JSONPath.read(string2, "..id");//相对路径
14 System.out.println(result03);
15 System.out.println(result031);
16 System.out.println(result0311.size()+" "+result0311.get(0));
17 System.out.println(result03111.size()+" "+result03111.get(0));
View Code
Json数据转换
1 //json数据转换
2 //String string21 = "{"total":641,"books":[{"id":"4866934","title":"Python基础教程"},{"id":"3117898","title":"Python源码剖析"},{"id":"3948354","title":"Python学习手册"},{"id":"3884108","title":"可爱的Python"}],"count":20,"start":0}
";
3 String string21 = "{"zz":"dd","total":641,"books":[{"zz":"dd","id":"4866934","title":"Python基础教程"},{"zz":"dd","id":"3117898","title":"Python源码剖析"},{"id":"3948354","zz":"dd","title":"Python学习手册"},{"zz":"dd","id":"3884108","title":"可爱的Python"}],"count":20,"start":0}";
4 JSONObject result04 = (JSONObject)JSON.parse(string21);
5 Map result041 = JSON.parseObject(string21, TreeMap.class);//下一层级转换成map 并进行排序
6 String result05 = JSON.toJSONString(JSON.parse(string21));
7
8 System.out.println(result04);
9 System.out.println(result041);
10 System.out.println(result05);
11
12 //自己构造json
13 JSONObject jsonObject= new JSONObject();
14 jsonObject.put("ds", "s");
15 jsonObject.put("dds", "ss");
16 System.out.println(jsonObject);
Json按照一个规则进行key排序
1 //json数据按照A-Z排序
2 //String string212 = "{"zz":"dd","total":641,"books":[{"zz":"dd","id":"4866934","title":"Python基础教程"},{"zz":"dd","id":"3117898","title":"Python源码剖析"},{"id":"3948354","zz":"dd","title":"Python学习手册"},{"zz":"dd","id":"3884108","title":"可爱的Python"}],"count":20,"start":0}";
3 String string212 = "{"zz":"dd","Zz":"dd","ZA":"dd","total":641,"books":[{"zz":"dd","id":"4866934","title":"Python基础教程"},{"zz":"dd","id":"3117898","title":"Python源码剖析"},{"id":"3948354","zz":"dd","title":"Python学习手册"},{"zz":"dd","id":"3884108","title":"可爱的Python"}],"count":20,"start":0}";
4 System.out.println(string212);
5 String tt =JSONObject.toJSONString((JSONObject)JSON.parse(string212),SerializerFeature.SortField.MapSortField);
6 System.out.println(tt);