How to autowire NamedParameterJdbcTemplate in Spring Boot - spring-boot

I understand that Spring Boot automatically configure JDBCTemplate for us. But i don't know exactly which way is correct when i want to autowire NamedParameterJdbcTemplate.
private NamedParameterJdbcTemplate template
or
private NamedParameterJdbcTemplate namedParameterJdbcTemplate;
P.S : i'm using Spring Boot 1.5.1 Release

I just found the answer by reading Spring Boot API, both ways are working and it does not depend on what we name it. Problem was solved.

Related

How can I get an ObjectMapper instance in Spring Boot without inheriting from spring-boot-starter-web?

I'm playing around with Spring Boot 2.0.0M2, trying to create a CLI application, not a web one. My problem is that even including
compile 'org.springframework.boot:spring-boot-starter'
compile 'org.springframework.boot:spring-boot-starter-json'
in my build, ObjectMapper is not created by Boot because
Bean method 'jacksonObjectMapper' not loaded because #ConditionalOnClass did not find required class 'org.springframework.http.converter.json.Jackson2ObjectMapperBuilder'
What's the best practice when you want to have Spring Boot instance and configure Jackson but don't want to start a web server?
You can add spring-boot-starter-json if you want to avoid to include the full web stack (since Spring Boot v.2.0.0M4).
Why don't you just initialize it yourself.
#Bean
ObjectMapper objectMapper() {
return new ObjectMapper();
}
You can try and JUST add org.springframework:spring-web dependency as that class is located in it.

Change Bean name for Bean implementations packaged in Jar - Spring Boot

I am using spring boot and Autowired NamedParameterJdbcTemplate as
#Autowired
private NamedParameterJdbcTemplate namedParameterJdbcTemplate;
I want to use different name for instance
private NamedParameterJdbcTemplate myTemplate;
How can this be achived in spring boot as I dont I have access to implementation class as I am using spring JDBC in POM as dependency.
Spring by default autowires the dependencies by Type reference not by name. Hence ur code will directly work without any changes required.
private NamedParameterJdbcTemplate myTemplate;
Spring will look for a bean of type NamedParameterJdbcTemplate and Autowire it, unless u have explicitly specified autowired by name. In the case of autowireby name u can use the #Qualifier to specify the bean name to autowire.
#Autowired
#Qualifier("beanName")

Spring Boot JPA CrudRepository

I'm working with Spring Boot + Spring Data JPA and facing this problem when trying to inject a class that extends CrudRepository:
Caused by: org.springframework.beans.factory.BeanCreationException:
Error creating bean with name 'topicRepository': Could not resolve
matching constructor (hint: specify index/type/name arguments for
simple parameters to avoid type ambiguities)
Repository Class:
public interface TopicRepository extends CrudRepository<Topic, Integer> {}
Service Class:
#Service
public class TopicService {
#Autowired
private TopicRepository topicRepository;
}
Any suggestions?
I was having the same issue, and I fixed it by switching Spring Boot versions. Changing the Spring Data JPA versions did nothing (this is where I assumed the bug would be), so I think there is a bug in Spring Boot version 1.5.1. I switched back to version 1.4.3 and the error was gone. I didn't try subsequent/different versions, so you may just have to experiment with your dependencies and their versions.
For the record, you can have your service class annotated with #Repository, it shouldn't make any difference. I've been setting these apps up the same way using the service/dao pattern, and it has never been too picky with the annotations. Hopefully this may help others whose Spring Boot development flow suddenly throws an error!
Which versions of spring-data-commons and spring-data-jpa are you using. I just ran into this using spring-data-commons 1.13.x with spring-data-jpa 1.10.x. Upgrading spring-data-jpa to 1.11.x fixed the issue for me.
I too had the same issue after updating Spring Boot to 1.5.4.
I am also using spring-data-envers, which was at version 1.0.4. Upgrading to 1.4.1 solved the problem.
I hope it helps someone :)
Make sure:
1) TopicRepository is annotated with #Repository.
2) You have the scanning packages configured:
<jpa:repositories base-package="mypkg.repositories"></jpa:repositories>
Had the same issue on 1.5.2. Upgrading to 1.5.5 solved the problem.
You can use Applicationcontext to inject repository to this reference topicRepository..
You just declare applicationcontext in #rest controller class
Same like topicRepository by using annotation. Then you pass this to the service class which should take parms through constructor.
Ex-
public TopicService(Applicationcontext ctx) {this.topicRepository =context.getBean(TopicRepository.class);
}

WebApplicationContext is always null in a spring boot test

My test class looks like this
#SpringBootTest(webEnvironment=WebEnvironment.MOCK)
public class sampleClassTest{
#Autowired
private WebApplicationContext wac;
}
#Before
public void setup() {
this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
}
In the setup method, wac is always null. From spring boot documentation, #SpringBootTest(webEnvironment=WebEnvironment.MOCK) always created a mock WebapplicaitonContext.
So I would expect it get autowired in the code above which doesn't happen.
Can someone tell me how to go about creating a webapplicationContext in this case so that it's not null like in my case ?
UPDATE
I am running spring boot tests invoking them from a class with springboot annotation.
Both test (springboottest) and calling class (springboot) application are in the same spring boot project under src/main/java.
I have nothing under src/main/test. I have done in this way because if classes from src/main/java want to call a test class then, it isn't really a test class.
Now, the problem is that I can't use runWith(SpringRunner.class) in springbootTest class. If I did that to get a mock webApplicationContext then, it gives me this error:
javax.management.InstanceAlreadyExistsException: org.springframework.boot:type=Admin,name=SpringApplication
I am not sure how to do about this.
To use #SpringBootTest you need to use Spring Framework's test runner. Annotate your test class with #RunWith(SpringRunner.class).
If someone is struggling with this issue in 2022 - please keep my defined precondions in mind. If you are using #SpringBootTest with defined port and constructor auto-wiring of the test class, the application context might be null.
It seems that the constructor dependency injection is eager and the cache aware context delegate of Spring is searching for a web application context which is no available yet. If you use field auto-wiring your test might run in a deterministic manner.
Whoever is facing this issue, make sure your spring boot starter parent version is compatible with spring cloud version in pom.xml
I was facing same issue, i resolved it by doing same.

Integrate Mongeez with Spring Boot and Spring Data MongoDB

I want to integrate Mongeez with my Spring Boot application and was wondering how to properly run Mongeez during application startup. Mongeez suggests creating a MongeezRunner bean. However, the challenge is to run Mongeez before any of the Spring Data initialization is happening, specifically, before the MongoTemplate instance is created. This is crucial because there might be changes in the database that prevent the application to start at all (e.g. changing index definitions).
My current approach is to provide the MongoTemplate bean myself, running Mongeez before creating it:
#Bean
public MongoTemplate mongoTemplate(Mongo mongo, MongoDbFactory mongoDbFactory,
MongoConverter converter) throws IOException {
// make sure that Mongeez runs before Spring Data is initialized
runMongeez(mongo);
return new MongoTemplate(mongoDbFactory, converter);
}
private void runMongeez(Mongo mongo) throws IOException {
Mongeez mongeez = new Mongeez();
mongeez.setMongo(mongo);
mongeez.setDbName(mongodbDatabaseName);
mongeez.setFile(new ClassPathResource("/db/migrations.xml"));
mongeez.process();
}
It works, but it feels like a hack. Is there any other way to do this?
After taking a look at Spring Boot's source code, it turns out that this problem isn't anything new. The FlywayAutoConfiguration for example has to make sure that Flyway (a migration tool for SQL-based databases) runs before any EntityManagerFactory beans are created. To achieve this the auto-configuration registers a BeanFactoryPostProcessor that dynamically makes every EntityManagerFactory bean depend on the Flyway bean, thus forcing Spring to create the Flyway bean first.
I solved my problem by creating a Spring Boot starter with a similar auto-configuration for Mongeez: mongeez-spring-boot-starter.

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