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How Spring Boot Application to listen for a CRUD operations

I am just starting with Spring boot Web Applications, and I am in this point now I need to issue notification in the app ecosystem after CRUD Operation in database (I am using MySQL)
How can I set up a listener and based on the operation to create a new notification. From my search, I land on #EntityListeners(AuditTrailListener.class) but not sure how to use it, I will be happy to share with me some examples or to redirect me to the right place to see how to set up that kind of listener.

Here's a collection of links which are providing some details about #EntityListeners with JPA in Spring Boot webapplications :
JPA Entity Lifecycle Events
A gist of a php-coder
Spring Data JPA Entity Auditing using EntityListeners
Spring JPA Auditing in Official Documentation
StackOverflow: How to use an #Autowired #EntityListener
StackOverflow: How to inject a dependency into a JPA #EntityListener
I think you'll have common paths to seek the information you need with all that links. And maybe other people will help you more.

Execution of neo4j cypher query from spring boot

Hi neo4j/spring boot masters
I am new to spring boot and I am trying to execute a cypher query without the #Query annotation.
I can see that my requirement is possible with entityManage.createQuery() in spring repository (javax)
But the adaptor for neo4j doesn't seem to have an entity Manager.
Any help is greatly appreciated.

I used the neo4j java driver in my spring boot as described at Using Neo4j from Java
This is maybe not what neo4j offers first, but i feel it is simple. You can also use it without transactions.

Depending on your needs, have a look at org.springframework.data.neo4j.core.Neo4jClient - specifically the query() method - if you have setup neo4j correctly in Spring then you can simply inject this class.

does Spring #transactional work with MongoDB?

I'm developing a web application with Spring Boot and MongoDB. I want to make the services work with the #transactional spring annotation, but I don't know if that really works. (I didn't work with mongoDB before).
I added the annotation and it seem that everything run fine (The application runs and I can do all operations CRUD), but, I don't know if Spring is ignoring the annotation and it is working as usual, or is really considering the transactionality.
In other post, I have seen that I should add a new bean in the configuration class, in order to enable the transactionlity between Spring and MongoDB. Is it really necessary?, I only use transactions with single Mongo documents.

#Transactional works only from spring-data-mongodb version 2.1.0 and higher:
https://docs.spring.io/spring-data/mongodb/docs/2.1.0.RELEASE/api/
Indeed you have to add the bean:
#Bean
MongoTransactionManager transactionManager(MongoDatabaseFactory dbFactory) {
return new MongoTransactionManager(dbFactory);
}
I don't know if Spring is ignoring the annotation and it is working as usual, or is really considering the transactionality
For this, you can throw an exception between 2 DB updates and check if the first update has been rolled back.
But if you use transactions within a single Mongo document, you don't need the #Transactional annotation:
In MongoDB, a write operation is atomic on the level of a single
document, even if the operation modifies multiple embedded documents
within a single document.
MongoDb documentation - Transactions

For Reactive style mongoDB & Spring boot integration the answer I provided here can be useful to people

Spring with Hibernate annotation based

I am looking at Spring documentation to learn Spring integration with Hibernate using annotation based spring configuration.
The documentation link is here.
Now the docs tell about how to configure Spring with Hibernate using xml files and there is no where mentioned how to use annotations for integrating Spring and Hibernate.
Please help me where can I find the explanation on Spring with Hibernate integration using annotations.

You can find the required annotations here - Annotations used for configuring DAO or Repository classes
Here is a good example for using Spring with Hibernate - Spring Hibernate Integration Using Annotations

http://examples.javacodegeeks.com/enterprise-java/hibernate/hibernate-jpa-dao-example/
I'm not sure if I should downvote you - you could easily find it on your own.
Ok, maybe it is not exactly Spring + Hibernate, but it really does not matter.

Convert Hibernate exceptions in Spring Roo to Spring Data Access exceptions

I am currently working on a Spring Roo project and I want the exceptions thrown by Hibernate to be converted to Spring Exceptions. E.g. I want the Hibernate exception ConstraintViolationException to be converted to Spring's DataIntegrityViolationException.
I have done this in Spring projects previously by adding in the following code to my Spring config:
<!-- Translates Hibernate exceptions to Spring Data Access Exceptions -->
<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>
However in Roo this does not work. Can anybody tell me how I can get this working and why it doesn't work in Roo?

You must setup the persistence layer as JPA Repository in order Roo configures your project to use Spring Data.
http://docs.spring.io/spring-roo/reference/html/base-layers.html#d4e1962