如何在非Spring管理的类中使用Spring加载的bean

        
            org.springframework.boot
            spring-boot-starter
        

        
            org.springframework.boot
            spring-boot-starter-test
            test
        

package com.example.demo;

public class Person {
    private String name;

    public Person() {
        System.out.println("person init ..");
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                '}';
    }
}

package com.example.demo;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;

public class ContextUtil{

    public ContextUtil () {

    }

    private static ApplicationContext applicationContext = null;

    public static void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        ContextUtil.applicationContext = applicationContext;
    }

    public static Object getObject(String beanName) {
        if (applicationContext == null) {
            throw new RuntimeException("applicationContext is null");
        }
        return applicationContext.getBean(beanName);
    }
}

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;

@SpringBootApplication
public class DemoApplication {

    public static void main(String[] args) {
        ApplicationContext context = SpringApplication.run(DemoApplication.class, args);
        ContextUtil.setApplicationContext(context); // 在这里把加载好的ApplicationContext设置到静态类中，以后通过这个类取Spring容器中的bean

        Person person = (Person)ContextUtil.getObject("p");
        System.out.println(person);
    }

    @Bean(name = "p")
    public Person person() {
        Person person = new Person();
        person.setName("小明");
        return person;
    }

}