Maven dependency conflicts with netty-all

Describe the issue

I am using S3AsyncClient as below:

S3AsyncClient client = S3AsyncClient.builder()
                .credentialsProvider(StaticCredentialsProvider.create(awsCreds))
                .endpointOverride(URI.create(configExt.getString(HOSTNAME)))
                .region(region)
                .build();

Due to maven depedency conflicts, I exclude some dependencies

             <groupId>software.amazon.awssdk</groupId>
            <artifactId>s3</artifactId>
                <exclusions>... more below...</exclusions>

Then I got a runtime error as below:

	 Caused by:java.lang.NoClassDefFoundError: io/netty/channel/ChannelFactory

Steps to Reproduce

When I added S3’s dependency to an existing project, which depends on

io.netty:netty-all:jar:4.0.36.Final:compile

I need to exclude some dependency as below to fix dependcy conflicts:

(the maven dependency conflict)

  Found in:
    io.netty:netty-transport:jar:4.1.61.Final:runtime
    io.netty:netty-all:jar:4.0.36.Final:compile
  Duplicate classes:...

<dependency>
            <groupId>software.amazon.awssdk</groupId>
            <artifactId>s3</artifactId>
            <exclusions>
                <exclusion>
                    <artifactId>netty-handler</artifactId>
                    <groupId>io.netty</groupId>
                </exclusion>
                <exclusion>
                    <artifactId>netty-codec-http</artifactId>
                    <groupId>io.netty</groupId>
                </exclusion>
                <exclusion>
                    <artifactId>netty-transport-native-unix-common</artifactId>
                    <groupId>io.netty</groupId>
                </exclusion>
                <exclusion>
                    <artifactId>netty-buffer</artifactId>
                    <groupId>io.netty</groupId>
                </exclusion>
                <exclusion>
                    <artifactId>netty-transport</artifactId>
                    <groupId>io.netty</groupId>
                </exclusion>
                <exclusion>
                    <artifactId>netty-codec</artifactId>
                    <groupId>io.netty</groupId>
                </exclusion>
                <exclusion>
                    <artifactId>netty-common</artifactId>
                    <groupId>io.netty</groupId>
                </exclusion>
                <exclusion>
                    <artifactId>netty-transport-native-epoll</artifactId>
                    <groupId>io.netty</groupId>
                </exclusion>
            </exclusions>
        </dependency>

After fixing the dependency errors I got the mentioned runtime error.

Current Behavior

The call stack is below:

	Caused by: java.lang.BootstrapMethodError: java.lang.NoClassDefFoundError: io/netty/channel/ChannelFactory
		at software.amazon.awssdk.http.nio.netty.SdkEventLoopGroup.resolveChannelFactory(SdkEventLoopGroup.java:145)
		at software.amazon.awssdk.http.nio.netty.SdkEventLoopGroup.<init>(SdkEventLoopGroup.java:79)
		at software.amazon.awssdk.http.nio.netty.SdkEventLoopGroup.<init>(SdkEventLoopGroup.java:62)
		at software.amazon.awssdk.http.nio.netty.SdkEventLoopGroup$DefaultBuilder.build(SdkEventLoopGroup.java:207)
		at software.amazon.awssdk.http.nio.netty.internal.SharedSdkEventLoopGroup.get(SharedSdkEventLoopGroup.java:57)
		at software.amazon.awssdk.http.nio.netty.NettyNioAsyncHttpClient$$Lambda$234/28553945.get(Unknown Source)
		at java.util.Optional.orElseGet(Optional.java:267)
		at software.amazon.awssdk.http.nio.netty.NettyNioAsyncHttpClient.eventLoopGroup(NettyNioAsyncHttpClient.java:148)
		at software.amazon.awssdk.http.nio.netty.NettyNioAsyncHttpClient.<init>(NettyNioAsyncHttpClient.java:89)
		at software.amazon.awssdk.http.nio.netty.NettyNioAsyncHttpClient.<init>(NettyNioAsyncHttpClient.java:67)
		at software.amazon.awssdk.http.nio.netty.NettyNioAsyncHttpClient$DefaultBuilder.buildWithDefaults(NettyNioAsyncHttpClient.java:680)
		at software.amazon.awssdk.core.internal.http.loader.DefaultSdkAsyncHttpClientBuilder.lambda$buildWithDefaults$0(DefaultSdkAsyncHttpClientBuilder.java:43)
		at software.amazon.awssdk.core.internal.http.loader.DefaultSdkAsyncHttpClientBuilder$$Lambda$232/19846366.apply(Unknown Source)
		at java.util.Optional.map(Optional.java:215)
		at software.amazon.awssdk.core.internal.http.loader.DefaultSdkAsyncHttpClientBuilder.buildWithDefaults(DefaultSdkAsyncHttpClientBuilder.java:43)
		at software.amazon.awssdk.core.client.builder.SdkDefaultClientBuilder.lambda$resolveAsyncHttpClient$8(SdkDefaultClientBuilder.java:285)
		at software.amazon.awssdk.core.client.builder.SdkDefaultClientBuilder$$Lambda$226/24154826.get(Unknown Source)
		at java.util.Optional.orElseGet(Optional.java:267)
		at software.amazon.awssdk.core.client.builder.SdkDefaultClientBuilder.resolveAsyncHttpClient(SdkDefaultClientBuilder.java:285)
		at software.amazon.awssdk.core.client.builder.SdkDefaultClientBuilder.finalizeAsyncConfiguration(SdkDefaultClientBuilder.java:236)
		at software.amazon.awssdk.core.client.builder.SdkDefaultClientBuilder.asyncClientConfiguration(SdkDefaultClientBuilder.java:181)
		at software.amazon.awssdk.services.s3.DefaultS3AsyncClientBuilder.buildClient(DefaultS3AsyncClientBuilder.java:28)
		at software.amazon.awssdk.services.s3.DefaultS3AsyncClientBuilder.buildClient(DefaultS3AsyncClientBuilder.java:22)
		at software.amazon.awssdk.core.client.builder.SdkDefaultClientBuilder.build(SdkDefaultClientBuilder.java:129)

Your Environment

• AWS Java SDK version used:

<dependency>
                <groupId>software.amazon.awssdk</groupId>
                <artifactId>bom</artifactId>
                <version>2.16.40</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>org.reactivestreams</groupId>
                <artifactId>reactive-streams</artifactId>
                <version>1.0.3</version>
            </dependency>
            <dependency>
                <groupId>io.netty</groupId>
                <artifactId>netty-codec-http</artifactId>
                <version>4.1.61.Final</version>
            </dependency>
            <!-- https://mvnrepository.com/artifact/io.netty/netty-handler -->
            <dependency>
                <groupId>io.netty</groupId>
                <artifactId>netty-handler</artifactId>
                <version>4.1.61.Final</version>
            </dependency>
            <!-- https://mvnrepository.com/artifact/io.netty/netty-codec-http -->
            <dependency>
                <groupId>io.netty</groupId>
                <artifactId>netty-codec-http</artifactId>
                <version>4.1.61.Final</version>
            </dependency>

• JDK version used: openjdk version “1.8.0_41”
• Operating System and version: Windows 10

[GingerMoon]

@debora-ito Thanks for the reply. I did do the same as you mentioned but still had the error. Our company’s policy (maven enforce) requires that all projects must depend on netty-all.jar, which has conflicts with aws-sdk-java-v2. Some of the maven errors are bleow:

  Found in:
    io.netty:netty-handler:jar:4.1.43.Final:runtime
    io.netty:netty-all:jar:4.0.36.Final:compile
  Duplicate classes:
    io/netty/handler/timeout/IdleStateHandler.class

[snehal-kolte]

@GingerMoon I am facing the same issue. As shown in the above screenshot, Would you please share how i can verify conflict dependencies? I am using intellij idk.