Dependencies issue, class not found is raised with 5.28.6

[dacr]

• org.neo4j.driver » neo4j-java-driver » 5.28.5

  • org.neo4j.bolt » neo4j-bolt-connection-netty » 2.0.0
    • io.netty » netty-handler » 4.1.119.Final

• org.neo4j.driver » neo4j-java-driver » 5.28.6

  • org.neo4j.bolt » neo4j-bolt-connection-netty » 5.0.0
    • io.netty » netty-handler » 4.2.2.Final

We have just upgraded to the 5.28.6 release of the driver and now we have class not found exception, looks like something is missing in the dependencies that you should provide :

java.lang.NoClassDefFoundError: io/netty/util/concurrent/Ticker
   at io.netty.handler.timeout.IdleStateHandler.<init>(IdleStateHandler.java:117)
   at io.netty.handler.timeout.IdleStateHandler.<init>(IdleStateHandler.java:172)
   at io.netty.handler.timeout.ReadTimeoutHandler.<init>(ReadTimeoutHandler.java:84)
   at org.neo4j.bolt.connection.netty.impl.async.inbound.ConnectTimeoutHandler.<init>(ConnectTimeoutHandler.java:34)
   at org.neo4j.bolt.connection.netty.impl.NettyConnectionProvider.lambda$installChannelConnectedListeners$2(NettyConnectionProvider.java:135)
   at io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:590)
   at io.netty.util.concurrent.DefaultPromise.notifyListeners0(DefaultPromise.java:583)
   at io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:559)
   at io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:492)
   at io.netty.util.concurrent.DefaultPromise.setValue0(DefaultPromise.java:636)
   at io.netty.util.concurrent.DefaultPromise.setSuccess0(DefaultPromise.java:625)
   at io.netty.util.concurrent.DefaultPromise.trySuccess(DefaultPromise.java:105)
   at io.netty.channel.DefaultChannelPromise.trySuccess(DefaultChannelPromise.java:84)
   at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.fulfillConnectPromise(AbstractNioChannel.java:305)
   at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.finishConnect(AbstractNioChannel.java:340)
   at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:776)
   at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:724)
   at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:650)
   at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:562)
   at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997)
   at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
   at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
   at java.base/java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: io.netty.util.concurrent.Ticker
   at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown Source)
   at java.base/java.lang.ClassLoader.loadClass(Unknown Source)
   ... 23 more

[injectives]

Hi.

It looks like a Netty versions conflict. 5.28.6 driver uses Netty 4.2.2. It fails because IdleStateHandler requires Ticker that is defined in netty-common.

My guess is that something in your dependency tree takes precedence and brings netty-common 4.1 that does not have Ticker type. And just more generally, having 2 conflicting Netty versions might be undesirable.

The options are:

1. Make sure all dependencies use Netty 4.2. By using mvn dependency:tree, it should be fairly easy to figure out what is going on.
2. Make driver use Netty 4.1 by importing netty-bom.
3. Use driver with shaded Netty. Artifact neo4j-java-driver-all.

Please give one of these options a try and let us know. Thank you!

[injectives]

Please get back to us if it is still an issue. Thank you.

[ikwattro]

The same issue appears for integration tests using DatabaseManagementService and a recent driver version with test scope, using neo4j-java-driver-all fixes the issue, thanks for the suggestion @injectives

[dacr]

Hi.

It looks like a Netty versions conflict. 5.28.6 driver uses Netty 4.2.2. It fails because IdleStateHandler requires Ticker that is defined in netty-common.

My guess is that something in your dependency tree takes precedence and brings netty-common 4.1 that does not have Ticker type. And just more generally, having 2 conflicting Netty versions might be undesirable.

The options are:

1. Make sure all dependencies use Netty 4.2. By using mvn dependency:tree, it should be fairly easy to figure out what is going on.
2. Make driver use Netty 4.1 by importing netty-bom.
3. Use driver with shaded Netty. Artifact neo4j-java-driver-all.

Please give one of these options a try and let us know. Thank you!

everything fine with neo4j-java-driver-all, thank you for the advice 😀 and sorry for the delay for this response