//字符串转化为JSON,取JSON内元素
String jsonStr="{'name':'Jeffrey'}";
JSONObject jo=JSONObject.fromObject(jsonStr);
System.out.println(jo); //{"name":"Jeffrey"}
String name = jo.get("name").toString();
System.out.println(name); //Jeffrey
jo.put("msg", "good");
System.out.println(jo); //{"name":"Jeffrey","msg":"good"}
//得到JOSN的String元素
System.out.println(jo.get("name")); //Jeffrey
String[] likes={"basketball","soccer","sport"};
jo.put("likes", likes);
System.out.println(jo);
//{"name":"Jeffrey","msg":"good","likes":["basketball","soccer","sport"]}
//得到JSON中的likes字符串数组的元素
JSONArray arrays = (JSONArray) jo.get("likes");
//遍历json数组
if(arrays.size()>0){
for(int i=0;i String str = arrays.getString(i); System.out.println(str); } } Map map.put("apples", "3kg"); map.put("suger", "1kg"); map.put("fish", "2tiao"); jo.put("map", map); System.out.println(jo); /*{"name":"Jeffrey","msg":"good","likes":["basketball","soccer","sport"], //获取map Map map1=(Map) jo.get("map"); System.out.println("\n-------------map-------------"); System.out.println(map1); //{"suger":"1kg","fish":"2tiao","apples":"3kg"} //获取map中的值 System.out.println(map.get("suger")); //1kg JSONObject jo=new JSONObject(); Map map.put("suger", "1kg"); map.put("fish", "2tiao"); Map map1.put("11", "aa"); map1.put("22", "bb"); Map map2.put("rr", "tt"); map2.put("dd", "ff"); Map [] maps={map,map1,map2}; jo.put("maps", maps); System.out.println(jo); /*{"name":"Ive","initial":"I", "likes":["basketball","soccer","sport"], "map":{"suger":"1kg","fish":"2tiao","apples":"3kg"}, "maps":[{"suger":"1kg","fish":"2tiao","apples":"3kg"}, {"22":"bb","11":"aa"},{"dd":"ff","rr":"tt"}]}*/ //得到maps集合数组。JSONArray是json数组 JSONArray ja=jo.getJSONArray("maps"); System.out.println("\n-------------maps-------------"); System.out.println(ja); //获取maps集合数组中的元素第一种方法,根据下标获取单个元素取值 JSONObject jo1 = new JSONObject().fromObject(ja.getString(0)); String str=jo1.get("fish").toString(); System.out.println(str); //获取maps集合数组中元素的第二种方法,遍历 if(ja.size()>0){ for(int i=0;i // 遍历 jsonarray 数组,把每一个对象转成 json 对象 JSONObject job = ja.getJSONObject(i); // 得到 每个对象中的属性值 System.out.print(job.get("suger")+"\t"); System.out.print(job.get("fish")+"\t"); System.out.println(job.get("apples")); } } //java对象转化为json对象 3.map集合与JSON相互转化
"map":{"suger":"1kg","fish":"2tiao","apples":"3kg"}} */ 4.map集合数组与JSON相互转化
5。Java对象与JSON相互转化
Emp emp=new Emp();
emp.setEmpNo(110);
emp.setEmpName("James");
emp.setLoc("KLFL");
JSONObject jo = JSONObject.fromObject(emp);
System.out.println(jo); //{"empName":"James","loc":"KLFL","empNo":110}
//json转化为java对象
Emp jsonEmp=(Emp) JSONObject.toBean(jo, Emp.class);
System.out.println(jsonEmp.getEmpName()); //James