configuration Elasticsearch to java SpringBoot Application

Question

I am trying to configure Elastic to SpringBoot Application with Jdk 1.8 and elastic search Versi7.6.61
and Current spring version 2.2.5.RELEASE

   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-parent</artifactId>
   <version>2.2.5.RELEASE</version>
   <relativePath/>

//these are pom for elastic search

<dependency>
      <groupId>org.elasticsearch</groupId>
      <artifactId>elasticsearch</artifactId>
      <version>${org.elasticsearch}</version>
    </dependency>

    <dependency>
      <groupId>org.elasticsearch.client</groupId>
      <artifactId>elasticsearch-rest-high-level-client</artifactId>
      <version>${org.elasticsearch}</version>
    </dependency>
    <dependency>
      <groupId>org.elasticsearch.client</groupId>
      <artifactId>elasticsearch-rest-client-sniffer</artifactId>
      <version>${org.elasticsearch}</version>
    </dependency>
       <dependency>
      <groupId>org.elasticsearch.client</groupId>
      <artifactId>transport</artifactId>
      <version>${org.elasticsearch}</version>
    </dependency> 

currently, I am using the latest release of Elasticsearch version 7.6.1 I got the following the Java JDK version is 1.8 Exception

     org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'elasticsearchRestHighLevelClient' defined in class path resource \[org/springframework/boot/autoconfigure/elasticsearch/rest/RestClientConfigurations$RestHighLevelClientConfiguration.class\]: Post-processing of merged bean definition failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class \[org.elasticsearch.client.RestHighLevelClient\] from ClassLoader \[sun.misc.Launcher$AppClassLoader@18b4aac2\]
            at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:572) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:879) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:878) ~\[spring-context-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~\[spring-context-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~\[spring-boot-2.2.3.RELEASE.jar:2.2.3.RELEASE\]
            at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) \[spring-boot-2.2.3.RELEASE.jar:2.2.3.RELEASE\]
            at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) \[spring-boot-2.2.3.RELEASE.jar:2.2.3.RELEASE\]
            at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) \[spring-boot-2.2.3.RELEASE.jar:2.2.3.RELEASE\]
            at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) \[spring-boot-2.2.3.RELEASE.jar:2.2.3.RELEASE\]
            at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) \[spring-boot-2.2.3.RELEASE.jar:2.2.3.RELEASE\]
            at io.dz.ReIndexing.main(ReIndexing.java:13) \[classes/:na\]
        Caused by: java.lang.IllegalStateException: Failed to introspect Class \[org.elasticsearch.client.RestHighLevelClient\] from ClassLoader \[sun.misc.Launcher$AppClassLoader@18b4aac2\]
            at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:481) ~\[spring-core-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.util.ReflectionUtils.doWithLocalMethods(ReflectionUtils.java:321) ~\[spring-core-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.buildLifecycleMetadata(InitDestroyAnnotationBeanPostProcessor.java:232) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.findLifecycleMetadata(InitDestroyAnnotationBeanPostProcessor.java:210) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessMergedBeanDefinition(InitDestroyAnnotationBeanPostProcessor.java:149) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessMergedBeanDefinition(CommonAnnotationBeanPostProcessor.java:310) ~\[spring-context-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyMergedBeanDefinitionPostProcessors(AbstractAutowireCapableBeanFactory.java:1094) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:569) ~\[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            ... 15 common frames omitted
        Caused by: java.lang.NoClassDefFoundError: org/elasticsearch/client/Cancellable
            at java.lang.Class.getDeclaredMethods0(Native Method) ~\[na:1.8.0_161\]
            at java.lang.Class.privateGetDeclaredMethods(Class.java:2701) ~\[na:1.8.0_161\]
            at java.lang.Class.getDeclaredMethods(Class.java:1975) ~\[na:1.8.0_161\]
            at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:463) ~\[spring-core-5.2.3.RELEASE.jar:5.2.3.RELEASE\]
            ... 22 common frames omitted
        Caused by: java.lang.ClassNotFoundException: org.elasticsearch.client.Cancellable
            at java.net.URLClassLoader.findClass(URLClassLoader.java:381) ~\[na:1.8.0_161\]
            at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~\[na:1.8.0_161\]
            at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:338) ~\[na:1.8.0_161\]
            at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~\[na:1.8.0_161\]
            ... 26 common frames omitted


//when I am trying to configure Elastic search I got the Exception class not Found 
thanks in Advance to reply][1]][1]  

Answer 1

When using springboot with elasticsearch, you need to be explicit with some transitive dependencies as SpringBoot declares a version 6.4...

Basically you can put this in your pom.xml:

<properties>
  <elasticsearch.version>7.6.1<elasticsearch.version>
</properties>

See documentation here: https://docs.spring.io/spring-boot/docs/current/reference/html/howto.html#howto-customize-dependency-versions

Answer 2

The high-level REST client which you have added internally calls low-level REST client

<dependency>
      <groupId>org.elasticsearch.client</groupId>
      <artifactId>elasticsearch-rest-high-level-client</artifactId>
      <version>${org.elasticsearch}</version>
</dependency>

This , low level client is loaded by core dependency itself, but it seems it does not correspond to version 7.x (You can check the same in your external libraries list).

In my system elastcsearch-rest-client that got added was of version 6.4.2 while I was using elastcisearch of version 7.5.0

So, in this case you can add dependency related to elasticsearch-rest-client manually in pom.xml by adding :

<dependency>
  <groupId> org.elasticsearch.client </ groupId>
  <artifactId> elasticsearch-rest-client </ artifactId>
  <version>${org.elasticsearch}</ version>
</ dependency>

So, your complete pom.xml related to elastic search dependencies should look like :

<dependency>
      <groupId>org.elasticsearch</groupId>
      <artifactId>elasticsearch</artifactId>
      <version>${org.elasticsearch}</version>
</dependency>

<dependency>
      <groupId>org.elasticsearch.client</groupId>
      <artifactId>elasticsearch-rest-high-level-client</artifactId>
      <version>${org.elasticsearch}</version>
</dependency>

<dependency>
      <groupId>org.elasticsearch.client</groupId>
      <artifactId>elasticsearch-rest-client-sniffer</artifactId>
      <version>${org.elasticsearch}</version>
</dependency>

<dependency>
      <groupId>org.elasticsearch.client</groupId>
      <artifactId>transport</artifactId>
      <version>${org.elasticsearch}</version>
</dependency>

<dependency>
      <groupId> org.elasticsearch.client </ groupId>
      <artifactId> elasticsearch-rest-client </ artifactId>
      <version>${org.elasticsearch}</ version>
</ dependency>