Listing all beans

It can be useful, especially for debugging purposes, to list all the beans at a given moment.

Getting ready

We will use the code from the Defining a bean implicitly with @Component recipe, where we defined a UserService bean.

How to do it…

Here are the steps to retrieve the names of the beans currently in Spring's ApplicationContext object:

1. In your class, add an ApplicationContext field annotated with @Autowired:

   @Autowired
   private ApplicationContext applicationContext;

2. In a method of that class, use ApplicationContext and its getBeanDefinitionNames()method to get the list of bean names:

   String[] beans = applicationContext.getBeanDefinitionNames();
   for (String bean : beans) {
     System.out.println(bean);
   }  

How it works…

When the controller class is instantiated, Spring automatically initializes the @Autowired field with its ApplicationContext object. The ApplicationContext object references all Spring beans, so we can get a list of all the beans that are using...