Does Spring have a main method?

2 Answers. Show activity on this post. Method main is an entry point for standalone applications, so if you want to use spring boot standalone application, usually (if not always) packaged into a JAR – then yes, you should use main method.

Where is main method in Spring?

The main method is deep in Servlet container that when you start will go and load war file into Java VM and delegate HTTP calls made to it to the appropriate Servlet that in turn will delegate to your Spring controller. For example when you run Tomcat startup.

What is the use of main method in spring boot?

A Spring Boot application’s main class is a class that contains a public static void main() method that starts up the Spring ApplicationContext. By default, if the main class isn’t explicitly specified, Spring will search for one in the classpath at compile time and fail to start if none or multiple of them are found.

Do we need main method in spring boot?

You don’t need the main method, all you need is to do is to extend SpringBootServletInitializer as Kryger mentioned. @SpringBootApplication public class Application extends SpringBootServletInitializer { @Override protected SpringApplicationBuilder configure(SpringApplicationBuilder application) { return application.

Can we have two main methods in Spring boot?

Now, let’s create a new Spring Main class in the application. After the creation of this class, we will have two new main classes with two public static void main(String args[]) methods. As we know from Java basics, we can only have one main method in a Java application.

What is Spring boot CommandLineRunner?

CommandLineRunner is a simple Spring Boot interface with a run method. Spring Boot will automatically call the run method of all beans implementing this interface after the application context has been loaded.

Can we have more than one @SpringBootApplication?

So yes, this is expected behavior given your project setup. Put each @SpringBootApplication class in a separate subpackage if you don’t want this to happen for local testing.

Can we have two main methods in spring boot?

Can a class have 2 main methods?

Yes, a Java program can contain more than one “main” method in a class. You can say by passing different arguments in the same main() method. This is called as overloading the main method.

What is @autowired annotation in spring boot?

The @Autowired annotation provides more fine-grained control over where and how autowiring should be accomplished. 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 the use of run method in Spring Boot?

Join the DZone community and get the full member experience. (Classname.class, args) bootstraps a spring application as a stand-alone application from the main method. It creates an appropriate ApplicationContext instance and load beans.

How do I start with spring getting started?

Like most Spring Getting Started guides, you can start from scratch and complete each step or you can bypass basic setup steps that are already familiar to you. Either way, you end up with working code. To start from scratch, move on to Starting with Spring Initializr. To skip the basics, do the following:

How to define the main class of a Spring Boot application?

In the project’s Gradle file, mainClassName can be defined within springBoot configuration block. This change made here is picked up by bootRun and bootJar task: springBoot { mainClassName = ‘cpm.baeldung.DemoApplication’ } Alternatively, the main class can be defined as the mainClassName property of bootJar Gradle task:

What are some examples of automatic configuration in Spring Boot?

These are just a few examples of the automatic configuration Spring Boot provides. At the same time, Spring Boot doesn’t get in your way. For example, if Thymeleaf is on your path, Spring Boot adds a SpringTemplateEngine to your application context automatically.