I was using the #ManyTOMany to function but the other doesn't have details provided by the id so may I know how to insert the row automatically at runtime if I give the id to it with default constraints?.
Don't know about your requirement but you can use #PostConstruct Annotation to do stuff at runtime.
#PostConstruct
public void checkData(){
// Do something ...
}
Related
In my Spring boot application i need to read data from a specific schema and write on another one, to do so i follow this guide (https://github.com/spring-projects/spring-data-examples/tree/main/jpa/multitenant/schema) and i used this answer (https://stackoverflow.com/a/47776205/10857151) to be able to change at runtime the schema used.
But if this works fine inside a service without any transaction scope, this doesn't works on a more complex architecture (exception: session/EntityManager is closed) where there are couple of service that share transaction to ensure rollback.
THE BELLOW IS A SIMPLE EXAMPLE OF THE ARCHITECTURE
//simple jpa repository
private FirstRepository repository;
private SecondRepository secondRepository;
private Mapper mapper;
private SchematUpdater schemaUpdater;
#Transactional
public void entrypoint(String idSource,String idTarget) {
//copy first object
firstCopyService(idSource, idTarget);
//copy second object
secondCopyService(idSource, idTarget);
}
#Transactional
public void firstCopyService(String idSource,String idTarget) {
//change schema to the source default
schemaUpdater.changeToSurceSchema();
Object obj=repository.get(idSource);
//convert obj before persist - set new id reference and other things
obj=mapper.prepareObjToPersist(obj,idTarget);
//change schema to the target default
schemaUpdater.changeToTargetSchema();
repository.saveAndFlush(obj);
}
#Transactional
public void secondCopyService(String idSource,String idTarget) {
schemaUpdater.changeToSurceSchema();
Object obj=secondRepository.get(idSource);
//convert obj before persist
obj=mapper.prepareObjToPersist(obj);
//change schema to the target default
schemaUpdater.changeToTargetSchema();
secondRepository.saveAndFlush(obj);
}
I need to know what could be the best solution to ensure this dynamical switch and maintain the transaction scope on each service, without causing problems connected to restore and clean entity manager session.
Thanks
I'm going to use #InsertOnlyProperty with Spring Boot 2.7 as it will take time for us to migrate to Spring Boot 3.0!
So I'm going to create my DataAccessStrategy based on the DefaultAccessStrategy and also override the SqlParametersFactory so that I can pass the RelationalPersistentProperty::isInsertOnly condition to the getParameterSource method, also overriding RelationalPersistentProperty by adding isInsertOnly. And is there a way to override RelationalPersistentProperty to add isInsertOnly property. Am I correct or is there a better solution than switching to Spring Boot 3.0 now. Thank you!
Since #InsertOnlyProperty is only supported for the aggregate root (in Spring Boot 3.0), one approach could be to copy the data to a surrogate object and use a custom method to save it. It would look something like this:
public record MyAggRoot(#Id Long id,
/* #InsertOnlyProperty */ Instant createdAt, int otherField) {}
public interface MyAggRootRepository
extends Repository<MyAggRoot, Long>, MyAggRootRepositoryCustom { /* ... */ }
public interface MyAggRootRepositoryCustom {
MyAggRoot save(MyAggRoot aggRoot);
}
#Component
public class MyAggRootRepositoryCustomImpl implements TaskRepositoryCustom {
#Autowired
private final JdbcAggregateOperations jao;
// Override table name which would otherwise be derived from the class name
#Table("my_agg_root")
private record MyAggRootForUpdate(#Id Long id, int otherField) {}
#Override
public MyAggRoot save(MyAggRoot aggRoot) {
// If this is a new instance, insert as-is
if (aggRoot.id() == null) return jao.save(aggRoot);
// Create a copy without the insert-only field
var copy = new MyAggRootForUpdate(aggRoot.id(), aggRoot.otherField());
jao.update(copy);
return aggRoot;
}
}
It is however a bit verbose so it would only be a reasonable solution if you only need it in a few places.
I build a Spring-Boot application that accesses a Database and extracts data from it. Everything is working fine, but I want to configure the table names from an external .properties file.
like:
#Entity
#Table(name = "${fleet.table.name}")
public class Fleet {
...
}
I tried to find something but I didn't.
You can access external properties with the #Value("...") annotation.
So my question is: Is there any way I can configure the table names? Or can I change/intercept the query that is sent by hibernate?
Solution:
Ok, hibernate 5 works with the PhysicalNamingStrategy. So I created my own PhysicalNamingStrategy.
#Configuration
public class TableNameConfig{
#Value("${fleet.table.name}")
private String fleetTableName;
#Value("${visits.table.name}")
private String visitsTableName;
#Value("${route.table.name}")
private String routeTableName;
#Bean
public PhysicalNamingStrategyStandardImpl physicalNamingStrategyStandard(){
return new PhysicalNamingImpl();
}
class PhysicalNamingImpl extends PhysicalNamingStrategyStandardImpl {
#Override
public Identifier toPhysicalTableName(Identifier name, JdbcEnvironment context) {
switch (name.getText()) {
case "Fleet":
return new Identifier(fleetTableName, name.isQuoted());
case "Visits":
return new Identifier(visitsTableName, name.isQuoted());
case "Result":
return new Identifier(routeTableName, name.isQuoted());
default:
return super.toPhysicalTableName(name, context);
}
}
}
}
Also, this Stackoverflow article over NamingStrategy gave me the idea.
Table names are really coming from hibernate itself via its strategy interfaces. Boot configures this as SpringNamingStrategy and there were some changes in Boot 2.x how things can be customised. Worth to read gh-1525 where these changes were made. Configure Hibernate Naming Strategy has some more info.
There were some ideas to add some custom properties to configure SpringNamingStrategy but we went with allowing easier customisation of a whole strategy beans as that allows users to to whatever they need to do.
AFAIK, there's no direct way to do config like you asked but I'd assume that if you create your own strategy you can then auto-wire you own properties to there. As in those customised strategy interfaces you will see the entity name, you could reserve a keyspace in boot's configuration properties to this and match entity names.
mytables.naming.fleet.name=foobar
mytables.naming.othertable.name=xxx
Your configuration properties would take mytables and within that naming would be a Map. Then in your custom strategy it would simply be by checking from mapping table if you defined a custom name.
Spring boot solution:
Create below class
#Configuration
public class CustomPhysicalNamingStrategy extends SpringPhysicalNamingStrategy{
#Value("${table.name}")
private String tableName;
#Override
public Identifier toPhysicalTableName(final Identifier identifier, final JdbcEnvironment jdbcEnv) {
return Identifier.toIdentifier(tableName);
}
}
Add below property to application.properties:
spring.jpa.properties.hibernate.physical_naming_strategy=<package.name>.CustomPhysicalNamingStrategy
table.name=product
My spring-data-jpa backend has a class that populates the (test) database with a lot of test data. The class usese the spring data repositories to create entities. All my entities have a field annotated with #CreatedData and the corresponding #EntityListeners(AuditingEntityListener.class) annotation on the model class. This works fine so far. dateCreated is automatically set correctly.
But when running Junit test I sometimes need to create a (test) object with a dateCreated in the past. How can I archive this? Only via plain JDBC?
In case you are using Spring Boot, you can mock dateTimeProvider bean used in EnableJpaAuditing annotation. Spring Data uses this bean to obtain current time at the entity creation/modification.
#Import({TestDateTimeProvider.class})
#DataJpaTest
#EnableJpaAuditing(dateTimeProviderRef = "testDateTimeProvider")
public class SomeTest {
#MockBean
DateTimeProvider dateTimeProvider;
...
It is necessary to define actual testDateTimeProvider bean, but it won't be used at all, as you will use mock instead.
You can write mockito methods afterwards as usual:
#Test
public void shouldUseMockDate() {
when(dateTimeProvider.getNow()).thenReturn(Optional.of(LocalDateTime.of(2020, 2, 2, 0, 0, 0)));
... actual test assertions ...
I found a way that works for me (using plain JDBC):
First I create my domain objects for testing with spring-data-jpa:
MyModel savedModel = myRepo.save(myModel);
That automatically fills the "dateCreated" with timestamp of "now". Since I need creation dates in the past for testing I manually tweak them with plain JDBC:
#Autowired
JdbcTemplate jdbcTemplate;
[...]
// This syntax is for H2 DB. For MySQL you need to use DATE_ADD
String sql = "UPDATE myTable SET created_at = DATEADD('DAY', -"+ageInDays+", NOW()) WHERE id='"+savedLaw.getId()+"'";
jdbcTemplate.execute(sql);
savedModel.setCreatedAt(new Date(System.currentTimeMillis() - ageInDays* 3600*24*1000);
Do not forget to also setCreatedAt inside the returned model class.
I do not know exact test case which you are using, but i can see few solutions:
create a mock object, once the dateCreated is called return date
month ago
maybe use in-mem db, populate it with date before test
go with AOP from the link provided in comments
I have requirement for spring mvc 3 caching. Requirement is : while starting the server, we need to call database for one dropdown and put those values in the cache. So that whenever we required those values, we need to retrieve from cache.
Please help me with an example.
Thanks in advance.
May be you can use init-method (Spring 2.5) or #PostConstruct annotation (in Spring 3.0).
This method will be called during server start up
The following is code snippet
#Component
public class CacheDBData {
private String values[];
//add setter & getter
//This will be called during server start up after properties are initialised
#PostConstruct
public void getDataFromDB() {
values = //Logic to get data from DB and store that in values property
}
}
Suppose for example you can use in class as follows
#controller
public class HomeController {
#Autowired
private CacheDBData cacheDBData ;
//getter and setters
private void methodxyz() {
String values[] = cacheDBData.getValues();
}
}
I've had success with Ehcahe for Spring. There's a couple of config files to setup but after that you simply annotate the methods you want to cache the output from and it just works.
This has the advantage that you can change the values coming back from the service/database and NOT have to restart your app, unlike the accepted answer.