java如何获取json的值 java如何获取json对象的值

第一步：

分析一下json字符串里到底有点啥……哦，有id，username，pwd和age

{"id":23,"username":"HUA","pwd":"15","age":15},{"id":24,"username":"LI","pwd":"15","age":14}

第二步

根据第一步的分析结果，准备好实体类User，放好get/set方法

package entity;

public class User {
	private int id;
	private String username;
	private String pwd;
	private int age;
	public int getAge() {
  	return age;
  }
	public void setAge(int age) {
  	this.age = age;
  }
	public int getId() {
  	return id;
  }
	public void setId(int id) {
  	this.id = id;
  }
	public String getPwd() {
  	return pwd;
  }
	public void setPwd(String pwd) {
  	this.pwd = pwd;
  }
	public String getUsername() {
  	return username;
  }
	public void setUsername(String username) {
  	this.username = username;
  }
}

第三步：

确定Json串格式是否如下（注意[和{，一般OPENAPI返回数据缺少前后两个方括号，注意自己补上→json=“[”+json+"]"）

[{"id":23,"username":"HUA","pwd":"15","age":15},{"id":24,"username":"LI","pwd":"15","age":14}]

第四步：

获取数据

json_map = "[{'id':23,'username':'HUA','pwd':'15','age':15},{'id':24,'username':'LI','pwd':'15','age':14}]";
JSONArray jsonarray = JSONArray.fromObject(json_map);
System.out.println(jsonarray);
System.out.println("------------");
List list = (List) JSONArray.toList(jsonarray, new User(), new JsonConfig());
Iterator it = list.iterator();
while (it.hasNext()) {
    User p = (User) it.next();
    System.out.println(p.getAge());//把age字段数据取出来了
}