添加 jsonschema2pojo-core 后嵌入式 Kafka 测试用例出错

Question

I have an application that created with Spring boot and Spring kafka libraries. Now I added jsonschema2pojo-core library to my pom file. After adding this jar file my test cases are failing with below error

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'embeddedKafka': Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: scala/runtime/java8/JFunction0$mcZ$sp Caused by: java.lang.NoClassDefFoundError: scala/runtime/java8/JFunction0$mcZ$sp

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.2.1.RELEASE</version>
    <relativePath />
</parent>

    <dependency>
        <groupId>org.springframework.kafka</groupId>
        <artifactId>spring-kafka</artifactId>
    </dependency>
    <!-- Test Dependencies -->
    <dependency>
        <groupId>org.springframework.kafka</groupId>
        <artifactId>spring-kafka-test</artifactId>
        <scope>test</scope>
    </dependency>

      <dependency>
        <groupId>org.jsonschema2pojo</groupId>
        <artifactId>jsonschema2pojo-core</artifactId>
        <version>1.0.2</version>
      </dependency>

Answer 1

It's probably similar to this https://docs.spring.io/spring-kafka/docs/2.5.11.RELEASE/reference/html/#jacksonscala-incompatibility

with the library pulling in an incompatible scala library.

Yes, adding

<dependency>
    <groupId>org.scala-lang</groupId>
    <artifactId>scala-library</artifactId>
    <version>2.12.11</version>
</dependency>

fixed it for me; but I can't guarantee that jsonschema2pojo will work with that version.

The scala folks are notorious for breaking API changes in patch releases.