java.lang.NoClassDefFoundError: io/netty/channel/group/ChannelMatchers

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Expert tip

A few things cause this exception:
1) Check if you have all jars and if they're in the correct path.
2) Your classpath might be broken, you can define it in the command line with java -cp yourClassPath or at your IDE if you're using one.


you can change your scala version to 2.11.11

Solutions on the web

via GitHub by almibe
, 1 year ago
via Google Groups by (JIRA), 11 months ago
via Google Groups by (JIRA), 11 months ago
at java.lang.ClassLoader.loadClass(
at sun.misc.Launcher$AppClassLoader.loadClass(
at java.lang.ClassLoader.loadClass(
at io.vertx.core.http.impl.HttpServerImpl.actualClose(
at io.vertx.core.http.impl.HttpServerImpl.close(
at io.vertx.core.impl.ContextImpl.runCloseHooks(
at io.vertx.core.impl.DeploymentManager$DeploymentImpl.lambda$null$2(
at io.vertx.core.impl.FutureImpl.checkCallHandler(
at io.vertx.core.impl.FutureImpl.complete(
at my.example.RestServerVerticle.stop(
at io.vertx.core.impl.DeploymentManager$DeploymentImpl.lambda$doUndeploy$3(
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(
at io.netty.util.concurrent.SingleThreadEventExecutor$

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