Getting error of NoClassDefFoundError Could not initialize class io.aiven.kafka.connect.opensearch.OpensearchSinkConnectorConfig

- I am not able to create a kafka connector for the opensearch by making the POST call to
- I have installed apache kafka from https://downloads.apache.org/kafka/3.4.0/kafka_2.12-3.4.0.tgz and have installed in windows machine.

```
// POST Request http://localhost:8083/connectors

// BODY (RAW JSON)
{
"name": "first-opensearch-connector",
"config": {
"connector.class": "io.aiven.kafka.connect.opensearch.OpensearchSinkConnector",
"connection.url": "http://localhost:9200/",
"tasks.max": "1",
"topics": "my_topic",
"key.ignore": "true",
"name": "first-opensearch-connector",
"connection.username": "admin",
"connection.password": "admin",
"value.converter": "org.apache.kafka.connect.json.JsonConverter",
"value.converter.schemas.enable": "false",
"schema.ignore": "true",
"type.name": "_doc"
}
}
```
- But got below error:
```
[2023-03-03 11:37:22,393] WARN /connectors/ (org.eclipse.jetty.server.HttpChannel:776)
javax.servlet.ServletException: org.glassfish.jersey.server.ContainerException: java.lang.NoClassDefFoundError: Could not initialize class io.aiven.kafka.connect.opensearch.OpensearchSinkConnectorConfig
at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:410)
at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:346)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:366)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:319)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:205)
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:799)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:554)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1624)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1440)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:188)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:505)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1594)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:186)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1355)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:191)
at org.eclipse.jetty.server.handler.StatisticsHandler.handle(StatisticsHandler.java:181)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127)
at org.eclipse.jetty.server.Server.handle(Server.java:516)
at org.eclipse.jetty.server.HttpChannel.lambda$handle$1(HttpChannel.java:487)
at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:732)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:479)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:277)
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:105)
at org.eclipse.jetty.io.ChannelEndPoint$1.run(ChannelEndPoint.java:104)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:883)
at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1034)
at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: org.glassfish.jersey.server.ContainerException: java.lang.NoClassDefFoundError: Could not initialize class io.aiven.kafka.connect.opensearch.OpensearchSinkConnectorConfig
at org.glassfish.jersey.servlet.internal.ResponseWriter.rethrow(ResponseWriter.java:254)
at org.glassfish.jersey.servlet.internal.ResponseWriter.failure(ResponseWriter.java:236)
at org.glassfish.jersey.server.ServerRuntime$Responder.process(ServerRuntime.java:438)
at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:263)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:248)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:244)
at org.glassfish.jersey.internal.Errors.process(Errors.java:292)
at org.glassfish.jersey.internal.Errors.process(Errors.java:274)
at org.glassfish.jersey.internal.Errors.process(Errors.java:244)
at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:265)
at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:234)
at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:680)
at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:394)
... 30 more
Caused by: java.lang.NoClassDefFoundError: Could not initialize class io.aiven.kafka.connect.opensearch.OpensearchSinkConnectorConfig
at io.aiven.kafka.connect.opensearch.OpensearchSinkConnector.config(OpensearchSinkConnector.java:77)
at org.apache.kafka.connect.runtime.AbstractHerder.validateConnectorConfig(AbstractHerder.java:487)
at org.apache.kafka.connect.runtime.AbstractHerder.lambda$validateConnectorConfig$2(AbstractHerder.java:377)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
... 1 more
[2023-03-03 11:37:22,415] WARN unhandled due to prior sendError (org.eclipse.jetty.server.HttpChannelState:787)
javax.servlet.ServletException: org.glassfish.jersey.server.ContainerException: java.lang.NoClassDefFoundError: Could not initialize class io.aiven.kafka.connect.opensearch.OpensearchSinkConnectorConfig
at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:410)
at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:346)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:366)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:319)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:205)
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:799)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:554)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1624)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1440)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:188)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:505)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1594)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:186)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1355)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:191)
at org.eclipse.jetty.server.handler.StatisticsHandler.handle(StatisticsHandler.java:181)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127)
at org.eclipse.jetty.server.Server.handle(Server.java:516)
at org.eclipse.jetty.server.HttpChannel.lambda$handle$1(HttpChannel.java:487)
at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:732)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:479)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:277)
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:105)
at org.eclipse.jetty.io.ChannelEndPoint$1.run(ChannelEndPoint.java:104)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:883)
at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1034)
at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: org.glassfish.jersey.server.ContainerException: java.lang.NoClassDefFoundError: Could not initialize class io.aiven.kafka.connect.opensearch.OpensearchSinkConnectorConfig
at org.glassfish.jersey.servlet.internal.ResponseWriter.rethrow(ResponseWriter.java:254)
at org.glassfish.jersey.servlet.internal.ResponseWriter.failure(ResponseWriter.java:236)
at org.glassfish.jersey.server.ServerRuntime$Responder.process(ServerRuntime.java:438)
at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:263)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:248)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:244)
at org.glassfish.jersey.internal.Errors.process(Errors.java:292)
at org.glassfish.jersey.internal.Errors.process(Errors.java:274)
at org.glassfish.jersey.internal.Errors.process(Errors.java:244)
at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:265)
at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:234)
at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:680)
at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:394)
... 30 more
Caused by: java.lang.NoClassDefFoundError: Could not initialize class io.aiven.kafka.connect.opensearch.OpensearchSinkConnectorConfig
at io.aiven.kafka.connect.opensearch.OpensearchSinkConnector.config(OpensearchSinkConnector.java:77)
at org.apache.kafka.connect.runtime.AbstractHerder.validateConnectorConfig(AbstractHerder.java:487)
at org.apache.kafka.connect.runtime.AbstractHerder.lambda$validateConnectorConfig$2(AbstractHerder.java:377)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
... 1 more
```
- And got below message in the postman:
```

Error 500 Request failed.

HTTP ERROR 500 Request failed.

URI:
/connectors/


STATUS:
500


MESSAGE:
Request failed.


SERVLET:
org.glassfish.jersey.servlet.ServletContainer-22c75c01

---

Powered by Jetty:// 9.4.48.v20220622

---

```