# Spring Boot – 獲取所有已加載的帶有類類型信息的 bean > 原文： [https://howtodoinjava.com/spring-boot/get-loaded-beans-class-type-in??formation/](https://howtodoinjava.com/spring-boot/get-loaded-beans-class-type-information/) Spring Boot 在內部加載了大量的 bean，以最小的配置運行您的應用程序。 在此示例中，我們將學習找出所有這些 **SpringBoot 加載的 Bean** 及其類類型信息。 ## 使用`ApplicationContext`獲取所有已加載的 bean 若要自動執行方法，請在應用程序完全加載后使用`CommandLineRunner`接口。[`CommandLineRunner`](https://docs.spring.io/spring-boot/docs/current/api/org/springframework/boot/CommandLineRunner.html)用于指示當 bean 包含在 Spring 應用程序中時，它應該**運行**。 1）使用`ApplicationContext.getBeanDefinitionNames()`查找所有已加載 bean 的名稱 2）使用`ApplicationContext.getBean(beanName)`獲取包含其運行時類型信息的 bean。 ```java package com.howtodoinjava.app.controller; import java.util.Arrays; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.CommandLineRunner; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.builder.SpringApplicationBuilder; import org.springframework.boot.web.support.SpringBootServletInitializer; import org.springframework.context.ApplicationContext; @SpringBootApplication public class SpringBootWebApplication extends SpringBootServletInitializer implements CommandLineRunner { @Override protected SpringApplicationBuilder configure(SpringApplicationBuilder application) { return application.sources(SpringBootWebApplication.class); } public static void main(String[] args) throws Exception { SpringApplication.run(SpringBootWebApplication.class, args); } @Autowired private ApplicationContext appContext; @Override public void run(String... args) throws Exception { String[] beans = appContext.getBeanDefinitionNames(); Arrays.sort(beans); for (String bean : beans) { System.out.println(bean + " of Type :: " + appContext.getBean(bean).getClass()); } } } ``` 運行上面的應用程序將在控制臺中打印 bean 名稱和類型信息，如下所示： ```java 2017-03-06 13:22:50 - Tomcat started on port(s): 8080 (http) basicErrorController of Type :: class org.springframework.boot.autoconfigure.web.BasicErrorController beanNameHandlerMapping of Type :: class org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping beanNameViewResolver of Type :: class org.springframework.web.servlet.view.BeanNameViewResolver characterEncodingFilter of Type :: class org.springframework.boot.web.filter.OrderedCharacterEncodingFilter conventionErrorViewResolver of Type :: class org.springframework.boot.autoconfigure.web.DefaultErrorViewResolver defaultServletHandlerMapping of Type :: class org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport$EmptyHandlerMapping defaultViewResolver of Type :: class org.springframework.web.servlet.view.InternalResourceViewResolver dispatcherServlet of Type :: class org.springframework.web.servlet.DispatcherServlet dispatcherServletRegistration of Type :: class org.springframework.boot.web.servlet.ServletRegistrationBean duplicateServerPropertiesDetector of Type :: class org.springframework.boot.autoconfigure.web.ServerPropertiesAutoConfiguration$DuplicateServerPropertiesDetector embeddedServletContainerCustomizerBeanPostProcessor of Type :: class org.springframework.boot.context.embedded.EmbeddedServletContainerCustomizerBeanPostProcessor error of Type :: class org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration$SpelView errorAttributes of Type :: class org.springframework.boot.autoconfigure.web.DefaultErrorAttributes ... ... ... ``` 我已經截斷了輸出。 您可以自己驗證整個列表。 學習愉快！