Can't connect java client to elasticsearch server

Question

I'm trying to connect my java client to an elasticsearch server.

Elasticsearch 2.4.0 is installed on a distant server. To access to it, I have to use port 10700. (When I run "telnet xxxx 10700", it worked, so the port is open)

I have an error for 2 days now and I read it could be a conflict between netty4 dependencies, but I'm not able to fix it. (My netty dependencies are transitives, I don't import them by myself)

How can I resolve this problem?

The java code:

public void connexionToEs() throws UnknownHostException {
    String clusterName = "xxxx";
    String serverAddress = "xxxx";

    try{
        Settings settings = Settings.builder()
                .put("cluster.name", clusterName)
                .put("client.transport.sniff", true)
                .build();
        TransportClient client = new PreBuiltTransportClient(settings);
        client.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName(serverAddress), 10700));

        SearchResponse response = client.prepareSearch().execute().actionGet();
        String output = response.toString();
        System.out.println(output);
        client.close();
    }catch(Exception e){
        e.printStackTrace();
    }
}

The dependencies:

<!-- DEPENDENCIES FOR ELASTICSEARCH CLIENT -->
<dependency>
  <groupId>org.elasticsearch</groupId>
  <artifactId>elasticsearch</artifactId>
  <version>5.2.0</version>
</dependency>

<dependency>
  <groupId>org.elasticsearch.client</groupId>
  <artifactId>transport</artifactId>
  <version>5.2.0</version>
</dependency>

<dependency>
  <groupId>org.apache.logging.log4j</groupId>
  <artifactId>log4j-api</artifactId>
  <version>2.6.2</version>
</dependency>
<dependency>
  <groupId>org.apache.logging.log4j</groupId>
  <artifactId>log4j-core</artifactId>
  <version>2.6.2</version>
</dependency>
<dependency>
  <groupId>org.apache.logging.log4j</groupId>
  <artifactId>log4j-web</artifactId>
  <version>2.6.2</version>
</dependency>
<dependency>
  <groupId>org.apache.logging.log4j</groupId>
  <artifactId>log4j-to-slf4j</artifactId>
  <version>2.6.2</version>
</dependency>

The error:

Exception in thread "elasticsearch[_client_][management][T#1]" java.lang.NoSuchMethodError: io.netty.buffer.CompositeByteBuf.addComponents(ZLjava/lang/Iterable;)Lio/netty/buffer/CompositeByteBuf;
at org.elasticsearch.transport.netty4.Netty4Utils.toByteBuf(Netty4Utils.java:78)
at org.elasticsearch.transport.netty4.Netty4Transport.sendMessage(Netty4Transport.java:422)
at org.elasticsearch.transport.netty4.Netty4Transport.sendMessage(Netty4Transport.java:93)
at org.elasticsearch.transport.TcpTransport.internalSendMessage(TcpTransport.java:1058)
at org.elasticsearch.transport.TcpTransport.sendRequestToChannel(TcpTransport.java:1040)
at org.elasticsearch.transport.TcpTransport.executeHandshake(TcpTransport.java:1555)
at org.elasticsearch.transport.TcpTransport.openConnection(TcpTransport.java:502)
at org.elasticsearch.transport.TcpTransport.connectToNode(TcpTransport.java:460)
at org.elasticsearch.transport.TransportService.connectToNode(TransportService.java:318)
at org.elasticsearch.client.transport.TransportClientNodesService$SniffNodesSampler$1.run(TransportClientNodesService.java:488)
at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingRunnable.run(ThreadContext.java:527)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)

The netty4 dependencies:

io.netty:netty:3.10.6.Final
io.netty:netty-buffer:4.0.28.Final
io.netty:netty-codec:4.0.28.Final
io.netty:netty-codec-http:4.1.7.Final
io.netty:netty-common:4.0.28.Final
io.netty:netty-handler:4.0.28.Final
io.netty:netty-resolver:4.1.7.Final
io.netty:netty-transport:4.0.28.Final

Answer 1

I solved a similar problem, with as following:

<dependency>
    <groupId>org.apache.hbase</groupId>
    <artifactId>hbase-client</artifactId>
    <version>1.3.0</version>
    <exclusions>
        <exclusion>
            <groupId>io.netty</groupId>
            <artifactId>netty-all</artifactId>
        </exclusion>
    </exclusions>
</dependency>

Answer 2

Please try using the matching Java dependency for your Elasticsearch server

<dependency>
    <groupId>org.elasticsearch</groupId>
    <artifactId>elasticsearch</artifactId>
    <version>2.4.0</version>
</dependency>