- What is spring bean life cycle?
- What is factory bean in spring?
- What’s the meaning of bean?
- What is BeanFactory and ApplicationContext?
- What is scope of bean in spring?
- What does the Spring bean lifecycle look like?
- What is difference between @inject and @autowired?
- What is bean class in spring?
- Why XmlBeanFactory is deprecated?
- What is bean factory?
- Can you describe the lifecycle of a spring bean in an ApplicationContext?
- Which of following is correct way to load bean definitions from another file?
- What is default bean scope in spring?
- Are all spring beans singletons?
- What is @qualifier in spring?
- How do I initialize a bean instance in spring?
- What is use of @autowired in spring?
- What is ContextClosedEvent event?
- Which is the way to provide configuration metadata to spring?
- What is the purpose of bean scope?
- What are different types of bean injections?
What is spring bean life cycle?
A “Spring bean” is just a Spring managed instantiation of a Java class.
The Spring IoC container is responsible for instantiating, initializing, and wiring beans.
The container also manages the life cycle of beans.
Spring provides several ways through which you can tap into the bean lifecycle..
What is factory bean in spring?
Conceptually, a factory bean is very similar to a factory method, but it is a Spring-specific bean that can be identified by the Spring IoC container during bean construction and can be used by container to instantiate other beans.
What’s the meaning of bean?
noun. the edible nutritious seed of various plants of the legume family, especially of the genus Phaseolus. a plant producing such seeds. the pod of such a plant, especially when immature and eaten as a vegetable. any of various other beanlike seeds or plants, as the coffee bean.
What is BeanFactory and ApplicationContext?
BeanFactory and ApplicationContext both are Java interfaces and ApplicationContext extends BeanFactory. Both of them are configuration using XML configuration files. In short BeanFactory provides basic Inversion of control(IoC) and Dependency Injection (DI) features while ApplicationContext provides advanced features.
What is scope of bean in spring?
The scope of the Spring singleton is best described as per container and per bean. This means that if you define one bean for a particular class in a single Spring container, then the Spring container will create one and only one instance of the class defined by that bean definition.
What does the Spring bean lifecycle look like?
Bean life cycle is managed by the spring container. When we run the program then, first of all, the spring container gets started. After that, the container creates the instance of a bean as per the request and then dependencies are injected. And finally, the bean is destroyed when the spring container is closed.
What is difference between @inject and @autowired?
The @Autowired annotation is used for auto-wiring in Spring framework. … The @Inject annotation also serves the same purpose, but the main difference between them is that @Inject is a standard annotation for dependency injection and @Autowired is spring specific.
What is bean class in spring?
In Spring, the objects that form the backbone of your application and that are managed by the Spring IoC container are called beans. A bean is an object that is instantiated, assembled, and otherwise managed by a Spring IoC container. Otherwise, a bean is simply one of many objects in your application.
Why XmlBeanFactory is deprecated?
Class XmlBeanFactory Deprecated. Convenience extension of DefaultListableBeanFactory that reads bean definitions from an XML document. … This class registers each bean definition with the DefaultListableBeanFactory superclass, and relies on the latter’s implementation of the BeanFactory interface.
What is bean factory?
A BeanFactory is like a factory class that contains a collection of beans. The BeanFactory holds Bean Definitions of multiple beans within itself and then instantiates the bean whenever asked for by clients. The BeanFactory is the actual container which instantiates, configures, and manages a number of beans.
Can you describe the lifecycle of a spring bean in an ApplicationContext?
When container starts – a Spring bean needs to be instantiated, based on Java or XML bean definition. It may also be required to perform some post-initialization steps to get it into a usable state. Same bean life cycle is for spring boot applications as well.
Which of following is correct way to load bean definitions from another file?
Just import the xml defining the bean with
What is default bean scope in spring?
Singleton is the default scope for a Bean, the one that will be used if nothing else is indicated. This scope implies that Spring container will create an only shared instance of the class designated by this bean, so each time the Bean is required the same object will be injected.
Are all spring beans singletons?
Spring’s default scope is singleton. … Only one shared instance of a singleton bean is managed, and all requests for beans with an id or ids matching that bean definition result in that one specific bean instance being returned by the Spring container.
What is @qualifier in spring?
The @Qualifier annotation is used to resolve the autowiring conflict, when there are multiple beans of same type. The @Qualifier annotation can be used on any class annotated with @Component or on method annotated with @Bean . This annotation can also be applied on constructor arguments or method parameters.
How do I initialize a bean instance in spring?
The order of bean initialization is same as it’s defined in the spring bean configuration file. The context is returned only when all the spring beans are initialized properly with post-init method executions. Employee name is printed as “Pankaj” because it was initialized in the post-init method.
What is use of @autowired in spring?
The @Autowired annotation can be used to autowire bean on the setter method just like @Required annotation, constructor, a property or methods with arbitrary names and/or multiple arguments. …
What is ContextClosedEvent event?
ContextClosedEvent. This event is published when the ApplicationContext is closed using the close() method on the ConfigurableApplicationContext interface. A closed context reaches its end of life; it cannot be refreshed or restarted.
Which is the way to provide configuration metadata to spring?
Configuration metadata can be provided to Spring container in following ways: XML-Based configuration: In Spring Framework, the dependencies and the services needed by beans are specified in configuration files which are in XML format.
What is the purpose of bean scope?
Only valid in the context of a web-aware Spring ApplicationContext. In Spring, bean scope is used to decide which type of bean instance should be returned from Spring container back to the caller. 5 types of bean scopes are supported : Singleton : It returns a single bean instance per Spring IoC container.
What are different types of bean injections?
We went through 4 types of dependency injection implemented by Spring framework:Constructor injection — good, reliable and immutable, inject via one of the constructors. … Setter injection — more flexible, mutable objects, injection via setters. … Field injection — fast and convenient, coupling with IoC container.More items…•