json的语法
Json应用
Json与XML的对比
json-lib
演示代码: /** * 演示JSON-LIB小工具 */ public class Demo1 { /* * 当map来用 */ @Test public void fun1() { JSONObject map = new JSONObject(); map.put("name", "zhangSan"); map.put("age", 23); map.put("sex", "male"); String s = map.toString(); System.out.println(s); } /* * 当你已经有一个Person对象时,可以把Person转换成JSONObject对象 */ @Test public void fun2() { Person p = new Person("liSi", 32, "female"); // 把对象转换成JSONObject类型 JSONObject map = JSONObject.fromObject(p); System.out.println(map.toString()); } /** * JSONArray */ @Test public void fun3() { Person p1 = new Person("zhangSan", 23, "male"); Person p2 = new Person("liSi", 32, "female"); JSONArray list = new JSONArray(); list.add(p1); list.add(p2); System.out.println(list.toString()); } /** * 原来就有一个List,我们需要把List转换成JSONArray */ @Test public void fun4() { Person p1 = new Person("zhangSan", 23, "male"); Person p2 = new Person("liSi", 32, "female"); List<Person> list = new ArrayList<Person>(); list.add(p1); list.add(p2); System.out.println(JSONArray.fromObject(list).toString()); } }
测试类: public class UserTest { @Test public void fun() { // str是一个json的文本数据 ,“\”为 双引号的转移符号 String str = "{\"name\":\"rose\"}"; JSONObject jsonObject = JSON.parseObject(str); System.out.println(jsonObject.get("name")); } }
测试类 public class UserTest { @Test public void fun() { String str = "[ {\"username\":\"rose\",\"password\":\"321\"}", {\"username\":\"jerry\",\"password\":\"123\"}" ]; User user = JSON.parseObject(str, User.class); System.out.println(user.getUsername()+":"+user.getPassword()); } } 运行后的结果: rose:321
测试类 public class UserTest { @Test public void fun() { String str = "[{\"username\":\"rose\",\"password\":\"321\"}," + "{\"username\":\"jerry\",\"password\":\"123\"}]"; List<User> list = JSON.parseArray(str, User.class); for (User u : list) { System.out.println(u.getUsername()+":"+u.getPassword()); } } 运行后的结果: rose:321 jerry:123
测试类 public class UserTest { @Test public void fun() { Date date = new Date(); System.out.println("date=" + date); String jsonString = JSON.toJSONString(date); System.out.println("--------------"); String dateFormat = JSON.toJSONStringWithDateFormat(date, "yyyy-MM-dd: hh:mm:ss"); System.out.println("dateFormat:"+dateFormat); } 运行后的结果: date=Wed Aug 22 19:08:06 CST 2018 <hr /> dateFormat:"2018-08-22: 07:08:06"
使用Maven进行搭建依赖
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.1.37</version>
</dependency>