I created a Spring Boot Starter Component
that depends on Kafka.
When I use the Starter Component
as one of the dependencies in other project it fails to start due a missing class from Kafka library:
Caused by: java.lang.ClassNotFoundException: org.springframework.kafka.config.ConcurrentKafkaListenerContainerFactory
If I explicitly put Kafka as a dependency in the other project it works, but I would expect it not being necessary since Kafka is a dependency from the Starter Component
and it should be resolved transiently
EXCEPTION
2022-12-03T14:05:42,321 DEBUG [main] o.s.b.StartupInfoLogger: Running with Spring Boot v2.7.0, Spring v5.3.20
2022-12-03T14:05:42,323 INFO [main] o.s.b.SpringApplication: The following 1 profile is active: "docker"
2022-12-03T14:05:43,161 INFO [main] o.s.d.r.c.RepositoryConfigurationDelegate: Bootstrapping Spring Data JPA repositories in DEFAULT mode.
2022-12-03T14:05:43,228 INFO [main] o.s.d.r.c.RepositoryConfigurationDelegate: Finished Spring Data repository scanning in 56 ms. Found 3 JPA repository interfaces.
2022-12-03T14:05:43,500 ERROR [main] o.s.b.SpringApplication: Application run failed
java.lang.IllegalStateException: Error processing condition on org.starter.autoconfigure.AppConfiguration.kafkaListenerContainerFactory
at org.springframework.boot.autoconfigure.condition.SpringBootCondition.matches(SpringBootCondition.java:60)
at org.springframework.context.annotation.ConditionEvaluator.shouldSkip(ConditionEvaluator.java:108)
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForBeanMethod(ConfigurationClassBeanDefinitionReader.java:193)
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForConfigurationClass(ConfigurationClassBeanDefinitionReader.java:153)
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitions(ConfigurationClassBeanDefinitionReader.java:129)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:343)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:247)
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:311)
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:112)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:746)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:564)
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:147)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:734)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:408)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:308)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1306)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1295)
at com.foo.bar.Application.main(Application.java:11)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:49)
at org.springframework.boot.loader.Launcher.launch(Launcher.java:108)
at org.springframework.boot.loader.Launcher.launch(Launcher.java:58)
at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:65)
Caused by: java.lang.IllegalStateException: @ConditionalOnMissingBean did not specify a bean using type, name or annotation and the attempt to deduce the bean's type failed
at org.springframework.boot.autoconfigure.condition.OnBeanCondition$Spec.validate(OnBeanCondition.java:494)
at org.springframework.boot.autoconfigure.condition.OnBeanCondition$Spec.<init>(OnBeanCondition.java:443)
at org.springframework.boot.autoconfigure.condition.OnBeanCondition.getMatchOutcome(OnBeanCondition.java:154)
at org.springframework.boot.autoconfigure.condition.SpringBootCondition.matches(SpringBootCondition.java:47)
... 25 more
Caused by: org.springframework.boot.autoconfigure.condition.OnBeanCondition$BeanTypeDeductionException: Failed to deduce bean type for org.starter.autoconfigure.AppConfiguration.kafkaLi
stenerContainerFactory
at org.springframework.boot.autoconfigure.condition.OnBeanCondition$Spec.deducedBeanTypeForBeanMethod(OnBeanCondition.java:524)
at org.springframework.boot.autoconfigure.condition.OnBeanCondition$Spec.deducedBeanType(OnBeanCondition.java:513)
at org.springframework.boot.autoconfigure.condition.OnBeanCondition$Spec.<init>(OnBeanCondition.java:436)
... 27 more
Caused by: java.lang.ClassNotFoundException: org.springframework.kafka.config.ConcurrentKafkaListenerContainerFactory
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at org.springframework.boot.loader.LaunchedURLClassLoader.loadClass(LaunchedURLClassLoader.java:151)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at org.springframework.boot.autoconfigure.condition.FilteringSpringBootCondition.resolve(FilteringSpringBootCondition.java:108)
at org.springframework.boot.autoconfigure.condition.OnBeanCondition$Spec.getReturnType(OnBeanCondition.java:532)
at org.springframework.boot.autoconfigure.condition.OnBeanCondition$Spec.deducedBeanTypeForBeanMethod(OnBeanCondition.java:520)
... 29 more
STARTER COMPONENT
package org.starter.autoconfigure;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.kafka.ConcurrentKafkaListenerContainerFactoryConfigurer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.kafka.annotation.EnableKafka;
import org.springframework.kafka.config.ConcurrentKafkaListenerContainerFactory;
import org.springframework.kafka.core.ConsumerFactory;
import org.springframework.kafka.listener.ContainerProperties;
import org.springframework.kafka.listener.KafkaMessageListenerContainer;
import org.starter.message.MyListener;
@Configuration
@EnableKafka
public class AppConfiguration
{
@Bean
@ConditionalOnMissingBean
public ConcurrentKafkaListenerContainerFactory<?, ?> kafkaListenerContainerFactory(
ConcurrentKafkaListenerContainerFactoryConfigurer configurer,
ConsumerFactory<Object, Object> kafkaConsumerFactory)
{
ConcurrentKafkaListenerContainerFactory<Object, Object> factory = new ConcurrentKafkaListenerContainerFactory<>();
configurer.configure(factory, kafkaConsumerFactory);
return factory;
}
@Bean
@ConditionalOnMissingBean
public KafkaMessageListenerContainer<String, String> messageListenerContainer(
ConsumerFactory<String, String> cf)
{
ContainerProperties containerProps = new ContainerProperties("my-topic");
containerProps.setMessageListener(new MyListener());
return new KafkaMessageListenerContainer<>(cf, containerProps);
}
}
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.7.0</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<modelVersion>4.0.0</modelVersion>
<groupId>org.starter</groupId>
<artifactId>component-starter</artifactId>
<version>1.0.3-SNAPSHOT</version>
<name>component-starter</name>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-autoconfigure</artifactId>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.kafka</groupId>
<artifactId>spring-kafka</artifactId>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.10</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.20</version>
</dependency>
</dependencies>
</project>
OTHER PROJECT
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.7.0</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>main-app</artifactId>
<version>1.0.0-SNAPSHOT</version>
<name>main-app</name>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-autoconfigure</artifactId>
</dependency>
<dependency>
<groupId>org.starter</groupId>
<artifactId>component-starter</artifactId>
<version>1.0.2-SNAPSHOT</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
It turned out to be a Nexus publishing issue. The starter component was being published with a generated pom.xml file without any dependency (without Kafka)
The issue was fixed when I published a new version pointing to a complete pom.xml file.
https://maven.apache.org/plugins/maven-deploy-plugin/examples/deploying-with-customized-pom.html