AbstractMethodError from gRPC client

[robertjli]

As soon as I add the dependency to my build.gradle file, I see this error when attempting to send a request.

frontend [warn] 2018-06-27 10:59:20 -0400 i.g.i.ManagedChannelImpl - [io.grpc.internal.ManagedChannelImpl-25] Unexpected exception from LoadBalancer
java.lang.AbstractMethodError: io.grpc.okhttp.OkHttpChannelBuilder$OkHttpTransportFactory.newClientTransport(Ljava/net/SocketAddress;Ljava/lang/String;Ljava/lang/String;Lio/grpc/internal/ProxyParameters;)Lio/grpc/internal/ConnectionClientTransport;
        at io.grpc.internal.CallCredentialsApplyingTransportFactory.newClientTransport(CallCredentialsApplyingTransportFactory.java:48)
        at io.grpc.internal.InternalSubchannel.startNewTransport(InternalSubchannel.java:209)
        at io.grpc.internal.InternalSubchannel.obtainActiveTransport(InternalSubchannel.java:188)
        at io.grpc.internal.ManagedChannelImpl$SubchannelImpl.requestConnection(ManagedChannelImpl.java:962)
        at io.grpc.util.RoundRobinLoadBalancerFactory$RoundRobinLoadBalancer.handleResolvedAddressGroups(RoundRobinLoadBalancerFactory.java:126)
        at io.grpc.internal.ManagedChannelImpl$NameResolverListenerImpl$1.run(ManagedChannelImpl.java:868)
        at io.grpc.internal.ChannelExecutor.drain(ChannelExecutor.java:72)
        at io.grpc.internal.ManagedChannelImpl$LbHelperImpl.runSerialized(ManagedChannelImpl.java:834)
        at io.grpc.internal.ManagedChannelImpl$NameResolverListenerImpl.onAddresses(ManagedChannelImpl.java:860)
        at io.grpc.internal.DnsNameResolver$1.run(DnsNameResolver.java:180)

Any thoughts?

[malafeev]

maybe jar hell? could you check that classpath doesn't have jars with different versions?

[robertjli]

CLASSPATH is empty. I'm a bit confused because we use netty as our transport layer in gRPC, so I'm not sure why it's requiring an okhttp class.

[malafeev]

@robertjli there is no dependency on okhttp:

/projects/java-grpc$ mvn dependency:tree 
[INFO] Scanning for projects...
[INFO] 
[INFO] --------------< io.opentracing.contrib:opentracing-grpc >---------------
[INFO] Building io.opentracing.contrib:opentracing-grpc 0.0.6-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
[INFO] --- maven-dependency-plugin:2.8:tree (default-cli) @ opentracing-grpc ---
[INFO] io.opentracing.contrib:opentracing-grpc:jar:0.0.6-SNAPSHOT
[INFO] +- io.opentracing:opentracing-api:jar:0.31.0:compile
[INFO] +- io.opentracing:opentracing-mock:jar:0.31.0:test
[INFO] |  +- io.opentracing:opentracing-noop:jar:0.31.0:test
[INFO] |  \- io.opentracing:opentracing-util:jar:0.31.0:test
[INFO] +- io.opentracing:opentracing-util:test-jar:tests:0.31.0:test
[INFO] +- io.grpc:grpc-core:jar:1.12.0:compile
[INFO] |  +- io.grpc:grpc-context:jar:1.12.0:compile
[INFO] |  +- com.google.code.gson:gson:jar:2.7:compile
[INFO] |  +- com.google.guava:guava:jar:20.0:compile
[INFO] |  +- com.google.errorprone:error_prone_annotations:jar:2.1.2:compile
[INFO] |  +- com.google.code.findbugs:jsr305:jar:3.0.0:compile
[INFO] |  +- io.opencensus:opencensus-api:jar:0.11.0:compile
[INFO] |  \- io.opencensus:opencensus-contrib-grpc-metrics:jar:0.11.0:compile
[INFO] +- io.grpc:grpc-stub:jar:1.12.0:test
[INFO] +- io.grpc:grpc-protobuf:jar:1.12.0:test
[INFO] |  +- com.google.protobuf:protobuf-java:jar:3.5.1:test
[INFO] |  +- com.google.protobuf:protobuf-java-util:jar:3.5.1:test
[INFO] |  +- com.google.api.grpc:proto-google-common-protos:jar:1.0.0:test
[INFO] |  \- io.grpc:grpc-protobuf-lite:jar:1.12.0:test
[INFO] +- io.grpc:grpc-netty:jar:1.12.0:test
[INFO] |  +- io.netty:netty-codec-http2:jar:4.1.22.Final:test (version selected from constraint [4.1.22.Final,4.1.22.Final])
[INFO] |  |  +- io.netty:netty-codec-http:jar:4.1.22.Final:test
[INFO] |  |  |  \- io.netty:netty-codec:jar:4.1.22.Final:test
[INFO] |  |  \- io.netty:netty-handler:jar:4.1.22.Final:test
[INFO] |  |     \- io.netty:netty-buffer:jar:4.1.22.Final:test
[INFO] |  |        \- io.netty:netty-common:jar:4.1.22.Final:test
[INFO] |  \- io.netty:netty-handler-proxy:jar:4.1.22.Final:test
[INFO] |     +- io.netty:netty-transport:jar:4.1.22.Final:test
[INFO] |     |  \- io.netty:netty-resolver:jar:4.1.22.Final:test
[INFO] |     \- io.netty:netty-codec-socks:jar:4.1.22.Final:test
[INFO] +- junit:junit:jar:4.12:test
[INFO] |  \- org.hamcrest:hamcrest-core:jar:1.3:test
[INFO] +- org.assertj:assertj-core:jar:3.9.1:test
[INFO] \- org.awaitility:awaitility:jar:3.1.0:test
[INFO]    +- org.hamcrest:hamcrest-library:jar:1.3:test
[INFO]    \- org.objenesis:objenesis:jar:2.6:test
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.694 s
[INFO] Finished at: 2018-06-28T13:49:08+08:00
[INFO] ------------------------------------------------------------------------
/projects/java-grpc$ 

could you attach your build.gradle file?

[robertjli]

It does seem like this is an issue on our side. Thanks for the help! I'll close the issue.