如何获取所有spring管理的bean

@Controller
public class FooController {
    @Autowired
    private FooService fooService;
    @RequestMapping(value="/displayallbeans") 
    public String getHeaderAndBody(Map model){
        model.put("header", fooService.getHeader());
        model.put("message", fooService.getBody());
        return "displayallbeans";
    }
}

@Service
public class FooService {
    public String getHeader() {
        return "Display All Beans";
    }
    public String getBody() {
        return "This is a sample application that displays all beans "
          + "in Spring IoC container using ListableBeanFactory interface "
          + "and Spring Boot Actuators.";
    }
}

@SpringBootApplication
public class Application {
    private static ApplicationContext applicationContext;
    public static void main(String[] args) {
        applicationContext = SpringApplication.run(Application.class, args);
        displayAllBeans();
    }
    public static void displayAllBeans() {
        String[] allBeanNames = applicationContext.getBeanDefinitionNames();
        for(String beanName : allBeanNames) {
            System.out.println(beanName);
        }
    }
}

[
    {
        "context": "application:8080",
        "parent": null,
        "beans": [
            {
                "bean": "fooController",
                "aliases": [],
                "scope": "singleton",
                "type": "com.baeldung.displayallbeans.controller.FooController",
                "resource": "file [E:/Workspace/tutorials-master/spring-boot/target
                  /classes/com/baeldung/displayallbeans/controller/FooController.class]",
                "dependencies": [
                    "fooService"
                ]
            },
            {
                "bean": "fooService",
                "aliases": [],
                "scope": "singleton",
                "type": "com.baeldung.displayallbeans.service.FooService",
                "resource": "file [E:/Workspace/tutorials-master/spring-boot/target/
                  classes/com/baeldung/displayallbeans/service/FooService.class]",
                "dependencies": []
            },
            // ...other beans
        ]
    }
]

ApplicationContext ctx = new ClassPathXmlApplicationContext("spring.xml");
              MyService myService1 = (MyService) ctx.getBean("myService");

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
 </beans>

// 装载实例化bean
       private Map<String, Object> beanMap = new HashMap<String, Object>();
       // 装载配置文件的属性和值
       private List<MyBeans> beanlist = new ArrayList<MyBeans>();      
       public MyClassPathXmlApplicationContext(String filename) {
              //第一步，解析spring配置文件
              readXml(filename);
              //第二步，通过反射，实例化所有注入bean
              initBeans();
       }
 
       
       private void initBeans() {
              for (MyBeans bean : beanlist) {
                     try {
                            if (bean.getClassName() != null && !"".equals(bean.getClassName())) {
                                   beanMap.put(bean.getId(), Class.forName(bean.getClassName()).newInstance());
                            }
                     } catch (Exception e) {
                            e.printStackTrace();
                     }
              }
       }
 
       
       private void readXml(String filename) {
              SAXReader reader = new SAXReader();
 
              Document doc = null;
              URL xmlpath = this.getClass().getClassLoader().getResource(filename);
              try {
                     Map<String, String> nsMap = new HashMap<String, String>();
                     nsMap.put("ns", "http://www.springframework.org/schema/beans");
                     doc = reader.read(xmlpath);
                     XPath xpath = doc.createXPath("//ns:beans//ns:bean");// 创建//ns:beans//ns:bean查询路径
                     xpath.setNamespaceURIs(nsMap);// 设置命名空间
                     List<Element> eles = xpath.selectnodes(doc);// 取得文档下所有节点
                     for (Element element : eles) {
                            String id = element.attributeValue("id");
                            String cn = element.attributeValue("class");
                            //自定义实体bean，保存配置文件中id和class
                            MyBeans beans = new MyBeans(id, cn);
                            beanlist.add(beans);
                     }
              } catch (Exception e) {
                     e.printStackTrace();
              }
 
       }
 
       public Object getBean(String beanId) {
              return beanMap.get(beanId);
       }

package com.mooing.service; 
public class MyBeans {
       private String id;
       private String className; 
       public MyBeans(String id, String className) {
              this.id = id;
              this.className = className;
       }
 
       public String getId() {
              return id;
       }
 
       public void setId(String id) {
              this.id = id;
       }
 
       public String getClassName() {
              return className;
       }
 
       public void setClassName(String className) {
              this.className = className;
       }
}

MyClassPathXmlApplicationContext ctx = new MyClassPathXmlApplicationContext("spring.xml");
  MyService myService = (MyService) ctx.getBean("myService");
  myService.save();