What is ment by servlet?

What is ment by servlet?

A servlet is a small program that runs on a server. The term was coined in the context of the Java applet, a small program that is sent as a separate file along with a Web (HTML) page. The “servlet” would indicate to the Web server that a servlet was being requested.

What is servlet in HTML?

A servlet is an extension to a server that enhances the server’s functionality. Web servers display documents written in HyperText Markup Language (HTML) and respond to user requests using the HyperText Transfer Protocol (HTTP).

Which lifecycle method is called once in servlet life?

Note: The init() method is called only once during the life cycle of servlet. Each time the web server receives a request for servlet, it spawns a new thread that calls service() method.

What is spring life cycle?

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 are advices in Spring?

Advice is an action taken by an aspect at a particular join point. Different types of advice include “around,” “before” and “after” advice. The main purpose of aspects is to support cross-cutting concerns, such as logging, profiling, caching, and transaction management.

What is use of @component in Spring?

@Component is an annotation that allows Spring to automatically detect our custom beans. In other words, without having to write any explicit code, Spring will: Scan our application for classes annotated with @Component. Instantiate them and inject any specified dependencies into them.

What is difference between @component and bean?

@Component is a class level annotation whereas @Bean is a method level annotation and name of the method serves as the bean name. @Component need not to be used with the @Configuration annotation where as @Bean annotation has to be used within the class which is annotated with @Configuration.

What is @ComponentScan?

Simply put – @ComponentScan tells Spring in which packages you have annotated classes which should be managed by Spring. Classes annotated with @Configuration is a new way of configuring Spring using annotations instead of XML files (it’s called Java configuration).

What is the use of component scan?

Using component scan is one method of asking Spring to detect Spring-managed components. Spring needs the information to locate and register all the Spring components with the application context when the application starts.

What is Spring bean Java?

By definition, a Spring bean is an object that form the backbone of your application and that is managed by the Spring IoC container. 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 bean is used 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.

What does Bean mean in Java?

In computing based on the Java Platform, JavaBeans are classes that encapsulate many objects into a single object (the bean). They are serializable, have a zero-argument constructor, and allow access to properties using getter and setter methods.

Why bean is used in Java?

Why use JavaBean? According to Java white paper, it is a reusable software component. A bean encapsulates many objects into one object so that we can access this object from multiple places. Moreover, it provides easy maintenance.

What is @bean used for?

Spring @Bean Annotation is applied on a method to specify that it returns a bean to be managed by Spring context. Spring Bean annotation is usually declared in Configuration classes methods. In this case, bean methods may reference other @Bean methods in the same class by calling them directly.