Spring boot app connecting to Elasticsearch error connection is closed

I am trying a simple example by connecting a Spring boot app to elasticsearch database, I have set up configuration as following

@Configuration
public class ElasticSearchConfig extends ElasticsearchConfiguration {
    @Override
    public ClientConfiguration clientConfiguration() {
        return ClientConfiguration.builder()
                .connectedTo("localhost:9200")
                .build();
    }
}

Springboot version: 3.2.0

Elasticsearch version: 8.11.1

Java: 21

I receive the following exception that fails to instantiate ElasticSearch Repository

aused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.data.elasticsearch.repository.support.SimpleElasticsearchRepository]: Constructor threw exception
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:223) ~[spring-beans-6.1.1.jar:6.1.1]
    at org.springframework.data.repository.core.support.RepositoryFactorySupport.lambda$instantiateClass$5(RepositoryFactorySupport.java:571) ~[spring-data-commons-3.2.0.jar:3.2.0]
    at java.base/java.util.Optional.map(Optional.java:260) ~[na:na]
    at org.springframework.data.repository.core.support.RepositoryFactorySupport.instantiateClass(RepositoryFactorySupport.java:571) ~[spring-data-commons-3.2.0.jar:3.2.0]
    at org.springframework.data.repository.core.support.RepositoryFactorySupport.getTargetRepositoryViaReflection(RepositoryFactorySupport.java:536) ~[spring-data-commons-3.2.0.jar:3.2.0]
    at org.springframework.data.elasticsearch.repository.support.ElasticsearchRepositoryFactory.getTargetRepository(ElasticsearchRepositoryFactory.java:79) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:317) ~[spring-data-commons-3.2.0.jar:3.2.0]
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.lambda$afterPropertiesSet$5(RepositoryFactoryBeanSupport.java:279) ~[spring-data-commons-3.2.0.jar:3.2.0]
    at org.springframework.data.util.Lazy.getNullable(Lazy.java:135) ~[spring-data-commons-3.2.0.jar:3.2.0]
    at org.springframework.data.util.Lazy.get(Lazy.java:113) ~[spring-data-commons-3.2.0.jar:3.2.0]
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.afterPropertiesSet(RepositoryFactoryBeanSupport.java:285) ~[spring-data-commons-3.2.0.jar:3.2.0]
    at org.springframework.data.elasticsearch.repository.support.ElasticsearchRepositoryFactoryBean.afterPropertiesSet(ElasticsearchRepositoryFactoryBean.java:69) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1822) ~[spring-beans-6.1.1.jar:6.1.1]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1771) ~[spring-beans-6.1.1.jar:6.1.1]
    ... 44 common frames omitted
Caused by: org.springframework.dao.DataAccessResourceFailureException: Connection is closed
    at org.springframework.data.elasticsearch.client.elc.ElasticsearchExceptionTranslator.translateExceptionIfPossible(ElasticsearchExceptionTranslator.java:110) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    at org.springframework.data.elasticsearch.client.elc.ElasticsearchExceptionTranslator.translateException(ElasticsearchExceptionTranslator.java:64) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    at org.springframework.data.elasticsearch.client.elc.ChildTemplate.execute(ChildTemplate.java:73) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    at org.springframework.data.elasticsearch.client.elc.IndicesTemplate.doExists(IndicesTemplate.java:177) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    at org.springframework.data.elasticsearch.client.elc.IndicesTemplate.exists(IndicesTemplate.java:169) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    at org.springframework.data.elasticsearch.repository.support.SimpleElasticsearchRepository.<init>(SimpleElasticsearchRepository.java:85) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    at java.base/jdk.internal.reflect.DirectConstructorHandleAccessor.newInstance(DirectConstructorHandleAccessor.java:62) ~[na:na]
    at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:502) ~[na:na]
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:486) ~[na:na]
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:210) ~[spring-beans-6.1.1.jar:6.1.1]
    ... 57 common frames omitted
Caused by: java.lang.RuntimeException: Connection is closed
    at org.springframework.data.elasticsearch.client.elc.ElasticsearchExceptionTranslator.translateException(ElasticsearchExceptionTranslator.java:63) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    ... 65 common frames omitted
Caused by: org.apache.http.ConnectionClosedException: Connection is closed
    at org.elasticsearch.client.RestClient.extractAndWrapCause(RestClient.java:920) ~[elasticsearch-rest-client-8.10.4.jar:8.10.4]
    at org.elasticsearch.client.RestClient.performRequest(RestClient.java:300) ~[elasticsearch-rest-client-8.10.4.jar:8.10.4]
    at org.elasticsearch.client.RestClient.performRequest(RestClient.java:288) ~[elasticsearch-rest-client-8.10.4.jar:8.10.4]
    at co.elastic.clients.transport.rest_client.RestClientHttpClient.performRequest(RestClientHttpClient.java:91) ~[elasticsearch-java-8.10.4.jar:na]
    at co.elastic.clients.transport.ElasticsearchTransportBase.performRequest(ElasticsearchTransportBase.java:137) ~[elasticsearch-java-8.10.4.jar:na]
    at co.elastic.clients.elasticsearch.indices.ElasticsearchIndicesClient.exists(ElasticsearchIndicesClient.java:655) ~[elasticsearch-java-8.10.4.jar:na]
    at org.springframework.data.elasticsearch.client.elc.IndicesTemplate.lambda$doExists$2(IndicesTemplate.java:177) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    at org.springframework.data.elasticsearch.client.elc.ChildTemplate.execute(ChildTemplate.java:71) ~[spring-data-elasticsearch-5.2.0.jar:5.2.0]
    ... 64 common frames omitted
Caused by: org.apache.http.ConnectionClosedException: Connection is closed
    at org.apache.http.nio.protocol.HttpAsyncRequestExecutor.endOfInput(HttpAsyncRequestExecutor.java:356) ~[httpcore-nio-4.4.16.jar:4.4.16]
    at org.apache.http.impl.nio.DefaultNHttpClientConnection.consumeInput(DefaultNHttpClientConnection.java:261) ~[httpcore-nio-4.4.16.jar:4.4.16]
    at org.apache.http.impl.nio.client.InternalIODispatch.onInputReady(InternalIODispatch.java:87) ~[httpasyncclient-4.1.5.jar:4.1.5]
    at org.apache.http.impl.nio.client.InternalIODispatch.onInputReady(InternalIODispatch.java:40) ~[httpasyncclient-4.1.5.jar:4.1.5]
    at org.apache.http.impl.nio.reactor.AbstractIODispatch.inputReady(AbstractIODispatch.java:114) ~[httpcore-nio-4.4.16.jar:4.4.16]
    at org.apache.http.impl.nio.reactor.BaseIOReactor.readable(BaseIOReactor.java:162) ~[httpcore-nio-4.4.16.jar:4.4.16]
    at org.apache.http.impl.nio.reactor.AbstractIOReactor.processEvent(AbstractIOReactor.java:337) ~[httpcore-nio-4.4.16.jar:4.4.16]
    at org.apache.http.impl.nio.reactor.AbstractIOReactor.processEvents(AbstractIOReactor.java:315) ~[httpcore-nio-4.4.16.jar:4.4.16]
    at org.apache.http.impl.nio.reactor.AbstractIOReactor.execute(AbstractIOReactor.java:276) ~[httpcore-nio-4.4.16.jar:4.4.16]
    at org.apache.http.impl.nio.reactor.BaseIOReactor.execute(BaseIOReactor.java:104) ~[httpcore-nio-4.4.16.jar:4.4.16]
    at org.apache.http.impl.nio.reactor.AbstractMultiworkerIOReactor$Worker.run(AbstractMultiworkerIOReactor.java:591) ~[httpcore-nio-4.4.16.jar:4.4.16]
    at java.base/java.lang.Thread.run(Thread.java:1583) ~[na:na]

Configuration needs to have elasticsearch username and password, and CA SHA-256 Fingerprint as well

This solved the problem and now it works fine

@Configuration
public class ElasticSearchConfig extends ElasticsearchConfiguration {
    @Override
    public ClientConfiguration clientConfiguration() {
        return ClientConfiguration.builder()
                .connectedTo("localhost:9200")
                .usingSsl("e0650a952ba6h5jb7d1ea9b3b8a59032j2005f675ec642jkg871038f27b2840d") //add the generated sha-256 fingerprint
                .withBasicAuth("elastic", "FnK9l206ZbUaI3kxzJKo") //add your username and password
                .build();
    }
}

These data can be found during startup of elasticsearch, it will output something like this

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✅ Elasticsearch security features have been automatically configured!
✅ Authentication is enabled and cluster connections are encrypted.

ℹ️  Password for the elastic user (reset with `bin/elasticsearch-reset-password -u elastic`):
  FnK9l206ZbUaI3kxzJKo

ℹ️  HTTP CA certificate SHA-256 fingerprint:
  e0650a952ba6h5jb7d1ea9b3b8a59032j2005f675ec642jkg871038f27b2840d

More configuration options can be found in documentation