使用fastjson对Json的基本操作

fastjson是阿里的一款对Json处理的工具，使用前需要引入对应的jar包下载地址

package json;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.alibaba.fastjson.JSON;

public class FastJsonDemo {

	//对象转Json
	public static String ClassToJson() {
		User user = new User();
		user.setId(\"1\");
		user.setName(\"王二麻子\");
		String json = JSON.toJSONString(user);
		return json;
		
	}
	
	//Json转对象
	public static User JsonToClass() {
		String classJson = ClassToJson();
		User user = JSON.parse (classJson,User.class);
		return user;
	}
	
	//List转Json
	public static String ListToJson() {
		List<User> userList = new ArrayList<>();
		userList.add(new User(\"1\",\"王一麻子\"));
		userList.add(new User(\"2\",\"王二麻子\"));
		userList.add(new User(\"3\",\"王三麻子\"));
		userList.add(new User(\"4\",\"王四麻子\"));
		userList.add(new User(\"5\",\"王五麻子\"));
		userList.add(new User(\"6\",\"王六麻子\"));
		String json = JSON.toJSONString(userList);
		return json;
		
	}
	
	//Json转List
	public static List<User> JsonToList(){
		String listJson = ListToJson();
		List<User> userList = JSON.parseArray(listJson,User.class);
		return userList;
	}
	
	//parse这个方法比较通用,但是无法精确泛型
	public static List JsonToList2() {
		String listJson = ListToJson();
		List userList = (List)JSON.parse(listJson);
		return userList;
	}
	
	//Map转Json
	public static String MapToJson() {
		Map<String,User> map = new HashMap<>();
		map.put(\"大哥\", new User(\"1\",\"李狗蛋子\"));
		map.put(\"二哥\", new User(\"2\",\"李猫蛋子\"));
		map.put(\"三哥\", new User(\"3\",\"李竹鼠蛋子\"));
		String json = JSON.toJSONString(map);
		return json;
	}
	
	//Json转Map
	public static Map JsonToMap() {
		String mapJson = MapToJson();
		Map map = (Map)JSON.parse (mapJson,Map.class);
		return map;
	}
	
	//通用的方法,但是无法确定泛型
	public static Map JsonToMap2() {
		String mapJson = MapToJson();
		//这2中写法都非常通用
		//Map map = (Map)JSON.parse(mapJson);
		Map map = JSON.parse (mapJson);
		return map;
	}
	
	public static void main(String[] args) {
		System.out.println(ClassToJson());//对象转Json
		System.out.println(JsonToClass());//Json转对象
		System.out.println(ListToJson());//List转Json
		JsonToList().forEach(x->System.out.println(x));//Json转List集合
		System.out.println(MapToJson());//Map转Json
		JsonToMap().forEach((x,y) -> {System.out.println(x+\":\"+y);});//Json转Map
	}
}

package json;

public class User {

	private String id;
	private String name;
	
	public User() {
		super();
	}
	public User(String id, String name) {
		super();
		this.id = id;
		this.name = name;
	}
	public String getId() {
		return id;
	}
	public void setId(String id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	@Override
	public String toString() {
		return \"User [id=\" + id + \", name=\" + name + \"]\";
	}
	
	
}