How to inject Bean of property within my context Bean? - spring-boot

Question

I'm trying to inject Bean of properties within context Bean.
(Spring-boot 2.7.3 / Java 11)
My application.yml is like below:
spring:
config:
active: dev
---
spring:
config:
activate:
on-profile: dev
keycloak:
username: "local"
password: "local"
---
spring:
config:
activate:
on-profile: stg
keycloak:
username: "stg"
password: "stg"
---
spring:
config:
activate:
on-profile: prod
keycloak:
username: "prod"
password: "prod"
and my KafkaProducerConfig.java code like below:
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.context.properties.ConstructorBinding;
import org.springframework.stereotype.Component;
import lombok.Getter;
#Getter
#Component
#ConstructorBinding
#ConfigurationProperties("keycloak")
public class KafkaProducerConfig {
private final String username;
private final String password;
public KafkaProducerConfig(String username, String password) {
this.username = username;
this.password = password;
}
}
and finally I failed to inject within another class.
Actually, UserDataProducer class extended in a context bean class which means UserDataProducer class also instanciated by spring IoC Container as I know.
I also tried #DependsOn which doesn't work.
#Slf4j
#DependsOn(value = {"KafkaProducerConfig"})
public class UserDataProducer {
#Autowired
KafkaProducerConfig kafkaProducerConfig;
private final String topicName;
public UserDataProducer() {
log.info("===========================================================");
log.info("Initializing UserDataProducer ...");
System.out.println(kafkaProducerConfig.getPassword());
log.info("===========================================================");
// additional properties for transactional producing
topicName = ProducerConfig.PRODUCER_PROPS.getProperty("default.topic");
}

Answer 1

#Slf4j
#Component
public class UserDataProducer {
// use static initializer block to initialize your static fields
// private static final Producer<String, Object> producer;
// initialzer order : static{} -> instance block {} -> constructor
private final String topicName;
public UserDataProducer(KafkaProducerConfig kafkaProducerConfig) {
log.info("===========================================================");
log.info("Initializing UserDataProducer ...");
System.out.println(kafkaProducerConfig.getPassword());
log.info("===========================================================");
// additional properties for transactional producing
topicName = ProducerConfig.PRODUCER_PROPS.getProperty("default.topic");
}