I am using Redis as cache with a spring boot project and i got to know there are two ways of using redis as cache for spring boot . First one is to use annotations like #cacheable , #cacheevict etc. and other to use redistemplate and to use methods like redistemplate.opsForHash().get(). I am confused about these two. What is the difference between the two and when to use what?
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I have a Spring Boot app with caching enabled using the #EnableCaching in the main class and #Cacheable for certain methods. This was earlier working well.
Now I have also configured GemFire cache to store other data.
The older code with the #Cacheable annotation is now trying to fetch this data in the GemFire cache. Is there a way to define when to use which cache?
I'm new to this and would appreciate any inputs on the best practice to be followed in such case and what can be done to overcome this.
Have a look at this: https://docs.spring.io/spring-boot-data-geode-build/current/reference/html5/#geode-caching-provider, and specifically this: https://docs.spring.io/spring-boot-data-geode-build/current/reference/html5/#geode-caching-provider-disable.
If you are not using Spring Boot for Apache Geode (SBDG; see project home as well as the docs) (which also applies to VMware Tanzu GemFire as well, given GemFire is based on OSS, Apache Geode), then you most definitely should consider it.
If you need to control which cache is used for which, e.g. service method, then you should read more about custom cache resolution as opposed to the default cache resolution strategy.
Last, SBDG honors Spring Boot's Caching configuration, after SBDG is essentially Spring Boot specifically designed and developed for Apache Geode (and GemFire).
I am building a Spring Boot rest API with Kotlin. I tried to find some information on how to do pagination in Spring Boot, because I want to return only some fixed amount of data at once (and then if requested, next chunk of information).
I was able to find tutorials and code samples where people used JPA and then it seemed to be relatively simple to have an interface that extends PagingAndSortingRepository. This is not possible for me, I'm using jdbc templates in DAO to access my DB. How can paging be done here without using JPA?
There are also interfaces Page and Pageable at my disposal, but can these be used without JPA? And if yes, how?
In my spring boot application spring #Transactional annotation works without specifying #EnableTransactionManagement explicitly.
Is there any official documentation saying that it is enabled automatically?
Or there is something else happening .... ?
btw: I'm using Spring Data JPA
Yes, this is enabled as long as you have spring-tx and some transactional resource in your application. Effectively if you are using spring-boot-starter-jdbc or spring-boot-starter-data-jpa, Spring Boot will configure a DataSource for you, start Hibernate (in the latter case) and configure transaction management.
Not all "Enable" annotations require to be explicitly set. When there is a reasonable amount of things that we can check to validate it makes sense to configure that for you, we'll do it. In this case, if you have a DataSource you must probably want to have transactions. If you have JPA (and no JTA infrastructure), you probably want a JpaTransactionManager). If we auto-configure that, the easiest way to use it is via #Transactional so we'll enable that in that case as well.
I guess you kept asking to get some sort of "official" answer, so here's one.
#SpringBootApplication adds #EnableAutoConfiguration it detects Spring Data JPA on your classpath. According to it Spring registers PlatformTransactionManager - JpaTransactionManager, datasource, entitymanager, repositories.
Not sure there are precise articles, but there are proper answer on stack. An official spring sample article
#Transactional annotation can work fine if the "< tx:annotation-driven/ >" tag is in your Spring XML configuration. Look at this reference : http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/transaction/annotation/EnableTransactionManagement.html
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 am planning to use Guice(for DI) and Jersey( for rest). They integrate very well but I also want to leverage what spring-data provides. But it seems like we need to integrate spring first to use Spring data*. Is there any way i can integrate spring-data* without using spring ioc container.
Yes. I did it. it seems spring data related beans should be manually wired.