目录
- 1、Map转JSON
- 2、**Map**转String
- 3、JSON转String
- 4、JSON转Map
- 5、String转JSON
- 6、将Json格式的字符串转换为对象
- 7、将map转换为对象
- 第二种 google
- 总结
1、Map转JSON
Map<String, Object> map = new HashMap<String, Object>();
("a", "a");
("b", "123");
JSONObject json = new JSONObject(map);
2、Map转String
Map<String, Object> map = new HashMap<>();
("a", "b");
String s = (map);
3、JSON转String
JSONObject json = new JSONObject();
("c", "v");
("z", "123n);
();
4、JSON转Map
JSONObject json = new JSONObject();
("ccc", "321");
("bbb", "123");
Map<String, Object> map = (Map<String, Object>)json;
5、String转JSON
String str = "{"username":"dsad","qwewqe":"123"}";
JSONObject json = (str);
6、将Json格式的字符串转换为对象
import ;
@Data
public class AlertRule {
private String relation;
private UpperLower diffAbs;
private UpperLower diffPercent;
}
@Data
public class UpperLower {
private BigDecimal upper;
private BigDecimal lower;
}
AlertRule alertRule= ("{\"diffAbs\":{\"upper\":2000,\"lower\":23000},\"diffPercent\":{\"upper\":2000,\"lower\":23000},\"relation\":\"OR\"}",);
(());
7、将map转换为对象
public class Test01 {
private static class Obj1 {
private String School;
private List<String> studen;
public List<String> getStuden() {
return studen;
}
public void setStuden(List<String> studen) {
= studen;
}
public String getSchool() {
return School;
}
public void setSchool(String school) {
School = school;
}
}
public static void main(String[] args) {
Map<String,String> map = new HashMap<>();
("studens","{\"city\":{\"School\":\"san\",\"studen\":[1,2,3]}}");
Map<String, Obj1> student = (("studens"), new TypeReference<Map<String,Obj1>>(){});
(student);
Set<<String,Obj1>> entries=();
for(<String,Obj1> aa:entries){
(aa);
Obj1 value=();
String school=();
(school);
List<String> studet=();
(studet);
}
}
}
第二种 google
maven坐标
<!-- /artifact//gson -->
<dependency>
<groupId></groupId>
<artifactId>gson</artifactId>
<version>2.3.1</version>
</dependency>
//Map转换成JSON
Map<String,String> map = new HashMap<String,String>();
("a","aaa");
("b","bbb");
("c","ccc");
String json=(map);
(json);//输出{"a":"aaa","b":"bbb","c":"ccc"}
//JSON转换成Map
Map map1 = (json);
(("a"));
for (Object mapData : ()) {
<String,String> entry = (<String,String>)mapData;
(()+"--->"+());
}
/*输出
b--->bbb
c--->ccc
a--->aaa
*/
map中含有对象Map -> JSON
//Map -> JSON
Map<String,Bar> map = new HashMap<String, Bar>();
("a",new Bar());
("b",new Bar());
("c",new Bar());
String json = (map,true);
(json);
/*
输出{
"a":{
"barAge":383687382,
"barDate":1494945882018,
"barName":"name_1689176802"
},
"b":{
"barAge":-100528778,
"barDate":1494945882018,
"barName":"name_-878176366"
},
"c":{
"barAge":-344075192,
"barDate":1494945882018,
"barName":"name_-1710740534"
}
}
*/
//JSON -> Map
Map<String,Bar> map1 = (Map<String,Bar>)(json);
for (String key : ()) {
(key+":"+(key));
}
/*输出
b:{"barAge":-100528778,"barDate":1494945882018,"barName":"name_-878176366"}
c:{"barAge":-344075192,"barDate":1494945882018,"barName":"name_-1710740534"}
a:{"barAge":383687382,"barDate":1494945882018,"barName":"name_1689176802"}
*/
-------------------=-------------------------附–MAP的ASCII排序-----------------------=------------------------
StringBuilder sb = new StringBuilder();
List<String> keys = new ArrayList<String>(());
(keys);//排序。
for(String k : keys){
String v = (k);
if((v)){
(v);
}
}
//return MD5.toMD5(sb+key, "UTF-8");这个就不用看了~~~
总结
public static void main(String[] args) {
JSONObject alertRule= ("{\"diffAbs\":{\"upper\":2000,\"lower\":23000},\"diffPercent\":{\"upper\":2000,\"lower\":23000},\"relation\":\"OR\"}");
//json--string
String a=(alertRule);
//string---json
JSONObject b=(a);
//json--map
Map json_map=(Map<String,Object>)b;
//map--string
String c=(json_map);
//map--json
JSONObject d=new JSONObject(json_map);
//string--map
Map<String,Object> e=(c,);
//map-对象
}
//转JSON
Map<String, Object> map1 = new HashMap<String, Object>();
map1.put("a", "a");
map1.put("b", "123");
JSONObject json = new JSONObject(map1);
System.out.println("map"+map1);
System.out.println("map->json"+json);
//转JSON
String str = "{\n" +
" \"username\":\"dsad\",\n" +
" \"qwewqe\":\"123\"\n" +
"}";
JSONObject json3 = JSONObject.parseObject(str);
System.out.println("string-json"+json3);
//转json string
Map<String, Object> map2 = new HashMap<>();
map2.put("a", "b");
String s = JSONObject.toJSONString(map2);
System.out.println("map"+map2);
System.out.println("map-string1"+JSON.toJSONString(map2));
System.out.println("map-string2"+s);
//转String
JSONObject json1 = new JSONObject();
json1.put("c", "v");
json1.put("z", "123n");
String ss=json.toJSONString(json1);
System.out.println("json-string"+ss);
//转Map
JSONObject json2 = new JSONObject();
json2.put("ccc", "321");
json2.put("bbb", "123");
Map<String, Object> maps = (Map<String, Object>)json2;
System.out.println("json->map"+maps);
System.out.println(maps.get("ccc"));
// string-map
String str1 = "{\n" +
" \"username\":\"dsad\",\n" +
" \"qwewqe\":\"123\"\n" +
"}";
Map newmap = JSON.parseObject(s, Map.class);
System.out.println("str->map"+newmap);
@Data
class User {
String name;
int age;
BigDecimal salary;
}
//对象和map之间的转换
User user = new User();
user.setName("校长");
user.setAge(3);
user.setSalary(new BigDecimal("123456789.0123"));
/*对象转map*/
String jsonString1 = JSON.toJSONString(user);
Map mapmap = JSON.parseObject(jsonString1, Map.class);
System.out.println("map = " + mapmap);// map = {name=校长, salary=123456789.0123, age=3}
String jsonString = JSON.toJSONString(mapmap);
User user1 = JSON.parseObject(jsonString, User.class);//json转对象
System.out.println("user1 = " + user1); //user1 = User{name='校长', age=3, salary=123456789.0123}
转载自：/web18296061989/article/details/123657550
如还看不懂，可参考案例：/u014212540/article/details/127687138