使用fastJSON解析HashMap中的数据

Posted 2020-09-17 MJBrian

import java.util.HashMap;  
 import java.util.Iterator;  
 import java.util.Map;  
 import java.util.Map.Entry;  
 import java.util.Set;  
  
 import com.alibaba.fastjson.JSON;  
 import com.alibaba.fastjson.TypeReference;  
  
  
public class Demo {  
    public static void main(String[] args) {  
        Map<String, Student> map = new HashMap<String, Student>();  
        Student stu1 = new Student("1", "莎拉波娃");  
        Student stu2 = new Student("2", "布沙尔");  
        Student stu3 = new Student("3", "哈勒普");  
  
  
        map.put("00011", stu1);  
        map.put("00012", stu2);  
        map.put("00013", stu3);  
  
  
        objectToStr(map);  
        String str = "{‘00011‘:{‘id‘:‘1‘,‘name‘:‘silei‘},‘00012‘:{‘id‘:‘2‘,‘name‘:‘布沙尔‘},‘00013‘:{‘id‘:‘3‘,‘name‘:‘哈勒普‘}}";  
        strToObject(str);  
    }  
  
  
    public static void strToObject(String str) {  
        Map<String, Student> map = (Map<String, Student>) JSON.parseObject(str, new TypeReference<Map<String, Student>>() {  
        });  
        Set<Entry<String, Student>> m = map.entrySet();  
        Iterator<Entry<String, Student>> it = m.iterator();  
        while (it.hasNext()) {  
            Entry<String, Student> en = it.next();  
            String id = en.getKey();  
            Student stu = en.getValue();  
            System.out.println(stu.getId() + "===" + stu.getName());  
        }  
        System.out.println(map.size());  
    }  
  
    // 把对象转换成JSON字符串  
    public static void objectToStr(Map map) {  
        String str = JSON.toJSONString(map);  
        System.out.println(str);  
    }  
}