I've noticed in our spring boot projects that during start up, spring seems to scan the classpaths for an implemented version of each of our DAOs.
We don't currently have implementations of our DAOs. We just extend the JPARepository and let spring data create the daos for us.
Is there any way to tell spring boot not to search for the implementations? We think it may help shave some time off of our start up times.
Related
I've found quite a huge pile of topics that give the answer for the opposite question: "Why choose Spring Boot over Spring?", but I guess somebody can give an example that will justify Spring selection over Spring Boot.
You can found several cons on Spring boot over Spring, mainly missing learning steps in Spring and support and if using monolithic application
If you are new to Spring and want to learn how the dependency injection, AOP programming, and proxies work, starting with Spring Boot is not a good choice. Spring Boot hides the most of these details from you.
If you are not familiarized with other projects of the Spring ecosystem (Spring Integration, Spring AMQP, Spring Security, etc), using them from Spring Boot will make you miss a lot of concepts
In a large and monolithic based applications, I wouldn’t encourage you to use Spring Boot
Also can increase deployment size
Spring boot may unnecessarily increase the deployment binary size with unused dependencies.
I have a maven project with many separate modules. I would like to move my Spring Boot JPA Entities (annotated with #javax.persistence.Entity) in a common module, and use that module as a dependency in Spring Boot.
The trouble is that when I do that, Spring Boot can no longer find data for those entities. It returns empty lists. My current workaround is to annotate the models with #MappedSuperclass in common and have dummy classes in Spring Boot which have the #Entity annotations and extend the classes in common. This is quite stupid though, there has to be a better way to do this.
Thanks.
I am trying to "really" understand Spring Framework. I have got some fair understanding of Spring Core (DI), and Spring MVC.
For data part, I am now focussing on Spring Data JPA. As I understand, JPA is a standard specification, for which there are multiple implementations, Hibernate being the famous one.
Now, when I started Spring Data JPA, I was under the impression that Spring Data JPA is an independent implementation of JPA specification. It turned out that I am wrong.
If I understood correctly, Spring Data JPA is an abstraction layer provided by Spring, which internally uses other JPA provider (Example Hibernate), so typically it is like this:
Application ---> Spring Data JPA --> Hiberate --> JDBC ----> DB
Is my understanding correct? If so isn't Spring Data JPA misleading? It is NOT a JPA provider in itself, it is just an abstraction layer, which works on top of other JPA provider.
I am not sure if I really understand Spring framework or it is a complex framework altogether?
Can anyone please help me understand it?
I don't think it's misnamed (disclaimer: I am the project lead). All Spring Data projects list the store or API they're based on in their name. Spring Data JPA is basically Spring Data for JPA, just like Spring Data MongoDB is Spring Data for MongoDB, just like Spring Batch is Spring for batch applications, Spring Integration is Spring for integration projects.
Do correct your dependency graph for JPA:
Application -> Spring Data JPA -> JPA <- Hibernate -> JDBC -> DataSource
-> — uses
<- — implements
The same for MongoDB:
Application -> Spring Data MongoDB -> MongoDB Java driver -> MongoDB
etc. I'd still be interested where exactly you got the impression that Spring Data JPA is an implementation of JPA as neither the project page nor the reference documentation state that anywhere. In fact, especially the project page is very explicit about what functionality the project provides. Also, it might help to study the description of the umbrella project, which tries to set some fundamental context for all the modules contained in it.
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.
I have a requirement that I have to use Spring Boot with JSF as user interface, as of now I am using JSF with spring other modules. So, I want know the similarities, differences and advantages of Spring boot over Spring other modules.
Long story short, Spring Boot is highly opinionated wrapper for Spring Framework with a lot of production and cloud ready features. It can significantly reduce amount of your configuration if you follow conventions.
Start reading here.
You can not compare spring boot and spring framework. Spring Boot is a new project aims to help spring development by auto configuration of things required to run the spring application.
So, if you have spring application, you can use spring boot to run your Spring application without worrying about writing the XML configuration.