There are many people who advised me to use Spring Boot instead of Spring to develop REST web services.
I want to know what exactly the difference between the two is?
In short
Spring Boot reduces the need to write a lot of configuration and boilerplate code.
It has an opinionated view on Spring Platform and third-party libraries so you can get started with minimum effort.
Easy to create standalone applications with embedded Tomcat/Jetty/Undertow.
Provides metrics, health checks, and externalized configuration.
You can read more here http://projects.spring.io/spring-boot/
Unfortunately and I mean this out of personal frustration with Spring boot, I have yet to see any real quantified list, where the differences are explicitly outlined.
There is only qualifications such as the rubbish sentence "...opinionated view..." which are bandied about.
What is clear, is that SpringBoot has wrapped up groups of Spring annotations into its own set of annotations, implicitly.
Further obfuscating, and making the need for anyone starting out in SpringBoot to have to commit to memory what a particular SpringBoot annotation represents.
My reply therefore is of no quantifiable benefit to the original question, which is analogous to that of the SpringBoot authors.
Those behind Spring IMO deliberately set-out to obfuscate, which reflects the obtuseness of their JavaDoc and API's (see SpringBatch API's as an example, if you think I am flaming) that makes one wonder the value of their open-source ethos.
My quest for figuring out SpringBoot continues.
Update. 22-08-2022
Read this (https://docs.spring.io/spring-boot/docs/current/reference/html/using.html#using.auto-configuration) and you will figure out for yourself what "opinionated" means.
There are over 140 Config classes that Springboot can use for this opinionated view, depending on what is on your classpath.
yes, on your classpath.
Finally and bizzarely, the annotation #SpringBootApplication is a configuration annotation as it includes it.
Go figure :=)
Basically, Spring Boot is an opinionated instance of a Spring application.
Spring Boot is a rapid application development platform. It uses various components of Spring, but has additional niceties like the ability to package your application as a runnable jar, which includes an embedded tomcat (or jetty) server. Additionally, Spring Boot contains a LOT of auto-configuration for you (the opinionated part), where it will pick and choose what to create based on what classes/beans are available or missing.
I would echo their sentiment that if you are going to use Spring I can't think of any reasons to do it without Spring Boot.
Spring Boot is opinionated view of Spring Framework projects.Let's analyse it through one program taken from Spring Boot Documentation.
#RestController
#EnableAutoConfiguration
public class Example {
#RequestMapping("/")
String home() {
return "Hello World!";
}
public static void main(String[] args) throws Exception {
SpringApplication.run(Example.class, args);
}
}
It's a very basic REST API and you need to add Spring-boot-starter-web in your POM.xml for the same. Since you have added starter-web dependency, the annotation
#EnableAutoConfiguration guesses that you want to develop a web application and sets up Spring accordingly.
Spring Boot auto-configuration attempts to automatically configure your Spring application based on the jar dependencies that you have added. For example, if HSQLDB is on your classpath, and you have not manually configured any database connection beans, then Spring Boot auto-configures an in-memory database.
It's opinionated like maven. Maven creates a project structure for you which it thinks is the general pattern of projects like it adds src/main/java folder or resource folder for you.
Spring boot helps in faster development. It has many starter projects that helps you get going quite faster. It also includes many non functional features like: embedded servers, security, metrics, health checks etc. In short, it makes, spring based application development easier with minimally invading code(Less configuration files, less no of annotations).
Reference: https://docs.spring.io/spring-boot/docs/current-SNAPSHOT/reference/htmlsingle/#boot-documentation-about
For developing common Spring applications or starting to learn Spring, I think using Spring Boot would be recommended. It considerably eases the job, is production ready and is rapidly being widely adopted.
Spring Boot is supposedly opinionated, i.e. it heavily advocates a certain style of rapid development, but it is designed well enough to accommodate exceptions to the rule, if you will. In short, it is a convention over configuration methodology that is willing to understand your need to break convention when warranted
For Spring Framework, you need to configure your project using XML configuration or Java configuration.
But for Spring Boot, these are preconfigured according to Spring team's view for rapid development. That is why Spring Boot is said to be an "opinionated view" of Spring Framework. It follows Convention over Configuration design paradigm.
Note: These configurations include view resolvers for MVC, transaction managers, way of locating container managed beans (Spring beans) and many more. And of course you can override any of these preconfigurations according to your need.
Spring Boot supports embedded servlet containers like Tomcat, Jetty or Undertow to create standalone applications, which Spring Framework doesn't.
Spring eliminate boilerplate code.
Spring-boot eliminates boilerplate configurations.
more
Related
I have a set of projects in Spring framework and I have to Find the ones which can be converted to Spring boot.
Is there anything that is related to Spring framework and cannot be converted to spring boot ? In my research, I Could not Find something like that.
But does anyone know something, like a dependency, which would force the project to stay in Spring framework ?
Spring Boot uses the Spring Framework as a foundation and improvises on it. It simplifies Spring dependencies and runs applications straight from a command line. Spring Boot provides several features to help manage enterprise applications easily. Spring Boot is not a replacement for the Spring, but it’s a tool for working faster and easier on Spring applications. It simplifies much of the architecture by adding a layer that helps automate configuration and deployment while making it easier to add new features.
Most of the changes for migrating Spring Framework application to Spring Boot are related to configurations.This migration will have minimal impact on the application code or other custom components.Spring Boot brings a number of advantages to the development.
It simplifies Spring dependencies by taking the opinionated view.
Spring Boot provides a preconfigured set of technologies/framework to reduces error-prone configuration so we as a developer focused on building our business logic and not thinking of project setup.
You really don’t need those big XML configurations for your project.
Embed Tomcat, Jetty or Undertow directly.
Provide opinionated Maven POM to simplify your configurations.
Application metrics and health check using actuator module.
Externalization of the configuration files.
Good to refer this for migrating from Spring to Spring Boot application: https://www.javadevjournal.com/spring-boot/migrating-from-spring-to-spring-boot/
I have just started learning spring boot . In its official page I found out this term and I did not understand that what actually it meant in Spring boot context.
Spring Boot just decides on a set of default configured beans which you can override if you want.
For example if you include the spring boot starter pom for jpa, you'll get autoconfigured for you an in memory database, a hibernate entity manager, and a simple datasource. This is an example of an opinionated (Spring's opinion that it's a good starting point) default configuration that you can override.
See https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#using-boot-replacing-auto-configuration
Spring Boot, is Spring on steroids if you will. It's a great way to get started very quickly with almost the entire Spring stack. I'll try to summarize as what "Opinionated Defaults Configuration" would mean in practice from a programmer's perspective below:
Helps you to setup a fully working application(web app or otherwise) very quickly by providing you intelligent default configurations that you are most likely to be satisfied to start with.
It does so by something called "AutoConfiguration", where capabilities from the Spring ecosystem of products are "auto-magically" enabled in your application by adding certain dependencies to your classpath; adding such dependencies via maven or gradle is super easy.
Most auto-configuration respects your own configuration, and backs off silently if you have provided your own configuration via your own beans.
You would benefit most if you take the java config approach of configuring your Spring application.
Super silky integration of new capabilities in your application by developing your own auto-configuration components (via annotations!).
Tons of auto-configaration components available ranging from Databases(h2, derby etc.), servlet containers(tomact, jetty etc.) to email and websockets are available. It is easy to develop your own. The important thing is that others can use those technology enablements in their own components. Please feel free to contribute.
Helps write very clean code with all the heavy lifting taken care of you, so that you can focus more on your business logic.
Hope you have fun with Spring Boot; its absolutely among the very best of frameworks to have hit the market in the last decade or so.
It follows opinionated default configuration so it reduces the developer efforts. Spring boot always uses sensible opinions, mostly based on the class path contents. So it overrides the default configuration.
I have been using Spring Boot and Spring Cloud for a while, and Spring core for even longer, yet I cannot find a clear rule on which technique to use when creating a framework :
Spring Boot starter + spring.factories file
Spring Boot starter + #EnableXxx
both
For example :
the Eureka client starter requires users to import spring-cloud-starter-eureka-client AND to add #EnableEurekaClient on some configuration class
On the other hand, adding spring-boot-starter-jdbc on the classpath is enough to trigger data source auto configuration. There is no such thing as #EnableDataSourceAutoConfiguration
Somebody who wants to configure caching through configuration properties also needs to add #EnableCaching manually
Sometimes the #EnableXxx annotated class is included in the code brought by a starter, sometimes not.
I know #Enable... is the "pre Spring-Boot" method (technically a good-looking #Import), but the fact that #EnableEurekaClient exists is proof that it's not deprecated by any mean.
What's the rule there ? I can't find it in the docs.
There's no hard and fast rule (at least from the Spring Cloud perspective).
Dave Syer said:
A candidate rule of thumb is "if something is on the classpath but
provides multiple features, you need a way to switch on a subset"
I prefer to think of it as "revealing a conscious choice"
as opposed to "relying on magic"
I've kind of looked at as starting servers or doing work (like Discovery Client)
I'm gradually introducing Spring Boot to a Spring JPA project. My intent was to first introduce Spring Boot, than at some later stage Spring Data, but I was not able to find any examples (nor a suitable starter) that uses Spring Boot + JPA without Spring Data.
How come? Is there any benefit of introducing Spring Boot to Spring JPA project, without Spring Data, or does it make sense only with Spring Data in place.
Any article link or example code would be helpfull and appreciated, thanks
More context
I'm working with a live project so every change introduces risk. We're discussing of moving from XML to JAVA based configuration, and I'm advocating adopting Spring Boot at a same time, but I lack persuasive selling points.
Personally, I want to include Spring Boot on all layers to boost future productivity, but I need to argue better the direct immediate benefits of using it in our Service/DAO module which is at the moment based on Spring/JPA/Hibernate with the good old manual CRUD implementations.
So I need selling points for using Spring Boot on a persistence layer, but ones that span beyond Spring Data (e.g. configuration gains, maintenance, testing...anything)
As folks have said above, there is no Spring Boot JPA. It's either Spring Boot Data JPA, or JPA on its own.
The immediate benefits that I could think of:
With Spring Data JPA you don't write the Dao layer. For all CRUD operations, the CrudRepository interface gives you all you need. When that is not enough, all you have to use is the #Query annotation to fine-tune your SQLs
Configuration by convention. For example, with Spring Boot, just having the H2 dependency in the classpath gets Spring to use the H2 in-memory database, gives you Datasource configuration and transaction management (only at the JPA repository level) by default
Ability to create micro-services. With Spring Boot, you can create micro services that can be deployed and run on a number of boxes with java -jar ...
You can enable annotation-based transaction with one simple annotation: #EnableTransactionManagement
Java configuration over XML. This advantage is not to be underestimated
A lot less code (the DAO layer) means also a lot less maintenance
The native ability to provide a RESTful API around data: https://spring.io/guides/gs/accessing-data-rest/
It all depends where your company is heading for. If they want to deliver business value faster and move towards more a DevOps operating model, then the above advantages should be enough selling points for any organisation
Spring wiht JPA (for example Hibernate) but without Spring-Data-Jpa means that you direct interact with the JPA Entity manager and. Typical you use it to implement your own DAO from it and use the #Respository annotation.
#Respository
public class UserDao {
#PersistenceContext EntityManager em;
public User findUserByLogin(Sting login) {
....
}
}
Even if there is no starter project, you could use a Spring-Data-JPA project, and implement the Repository in this old fashion style. (And then you could show how simple it become when you just write Spring-Data-JPA interfaces)
As far as I known, spring-boot means more convenient not any independent business feature.
In other words, spring-boot helps you to start, configure your application in some automatically way. But you can do that without spring-boot with your own specific configuration.
So, you are going to use spring-boot in your application means you are going to use spring-boot's auto configuration feature with your original application.
Actually, Spring JPA implemented in spring-data-jpa is what you are looking for not spring-boot. Of course, spring-boot can simplify your work dramatically.
Spring 4.0 has improved support for Groovy e.g. using the GroovyBeanDefinitionReader.
What would be setup to to have a full Spring MVC application using Groovy?
E.g. using GroovyBeanDefinitionReader and AnnotationConfigWebApplicationContext together.
Anyone knows if there is a sample available or some pointers on a blog site?
You might want to check out spring boot, still in milestone release behind Spring 4 but they were really pushing its groovy support at spring eXchange.
Check out the bottom of this spring-boot guide
It's not quite the use of GroovyBeanDefinitionReader and AnnotationConfigWebApplicationContext you asked for, but I can't see why you couldn't do what you are after with the opinionated approach used by spring boot and the standard configuration annotations on groovy classes.
The git hub repository shows a number of annotated groovy examples
with ui.groovy for example, showing a configuration class for the WebMvcConfigurerAdapter defining a bean.
In your main method, do SpringApplication.run(new Object[]{JavaConfig.class, "beans.groovy"}, args), where JavaConfig contains your configurations in java (like #Configuration, #ComponentScan and etc., I generally find these things are easier using annotations) and beans.groovy just contain your spring beans DSL.
Assuming beans.groovy is on classpth (i.e. under src/main/resources)