I am getting this error when I try to connect to Cassandra from Java using DataStax Java Driver. I have read few answer on SO. Here it says com.google.common.util.concurrent.FutureFallback is deprecated
in Guava 19.0 and removed since Guava 20.0. So, do not use Guava 20.0 or greater.
Moreover, I am using Pmml-Evaluator which requires Guava 20.0. My code works fine if I remove this code of connecting to Cassandra. So, how do i resolve this now?
Pom.xml dependencies :
<dependencies>
<dependency>
<groupId>org.jpmml</groupId>
<artifactId>pmml-model</artifactId>
<version>1.3.4</version>
</dependency>
<dependency>
<groupId>com.beust</groupId>
<artifactId>jcommander</artifactId>
<version>1.48</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.jpmml</groupId>
<artifactId>pmml-evaluator</artifactId>
<version>1.3.4</version>
</dependency>
<dependency>
<groupId>io.grpc</groupId>
<artifactId>grpc-netty</artifactId>
<version>1.1.2</version>
</dependency>
<dependency>
<groupId>io.grpc</groupId>
<artifactId>grpc-protobuf</artifactId>
<version>1.1.2</version>
</dependency>
<dependency>
<groupId>io.grpc</groupId>
<artifactId>grpc-stub</artifactId>
<version>1.1.2</version>
</dependency>
<dependency>
<groupId>io.netty</groupId>
<artifactId>netty-handler</artifactId>
<version>4.1.8.Final</version>
</dependency>
<dependency>
<groupId>com.datastax.cassandra</groupId>
<artifactId>cassandra-driver-core</artifactId>
<version>3.1.4</version>
</dependency>
</dependencies>
Class :
package com.cw.predictive;
import com.datastax.driver.core.Session;
import com.datastax.driver.core.Cluster;
public class CassandraSession {
private static Session session;
private CassandraSession(){}
public static Session getCassandraSessionInstance(String[] CONTACT_POINTS, int PORT){
if(session == null){
synchronized (Session.class) {
if(session == null){
try{
Cluster cluster = Cluster.builder()
.addContactPoints(CONTACT_POINTS).withPort(PORT)
.build();
session = cluster.connect();
}
catch(Exception ex) {
System.out.println("Error occurred");
return null;
}
}
}
}
return session;
}
}
Error:
Exception in thread "grpc-default-executor-0" java.lang.NoClassDefFoundError: com/google/common/util/concurrent/FutureFallback
at com.cw.predictive.CassandraSession.getCassandraSessionInstance(CassandraSession.java:18)
at com.cw.predictive.PredictiveScore$LeadScoreImpl.getLeadScore(PredictiveScore.java:136)
at com.cw.predicitivegrpc.LeadScoreGrpc$MethodHandlers.invoke(LeadScoreGrpc.java:234)
at io.grpc.stub.ServerCalls$1$1.onHalfClose(ServerCalls.java:148)
at io.grpc.internal.ServerCallImpl$ServerStreamListenerImpl.halfClosed(ServerCallImpl.java:263)
at io.grpc.internal.ServerImpl$JumpToApplicationThreadServerStreamListener$2.runInContext(ServerImpl.java:586)
at io.grpc.internal.ContextRunnable.run(ContextRunnable.java:52)
at io.grpc.internal.SerializingExecutor$TaskRunner.run(SerializingExecutor.java:152)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassNotFoundException: com.google.common.util.concurrent.FutureFallback
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 11 more
As you have encountered, the DataStax Java Driver for Apache Cassandra does not support Guava 20 and 21 yet (see: JAVA-1328).
However, there is a working PR that has been tested for Guava 16.01, 17.0, 18.0, 19.0, 20.0 and 21.0 and we are targetting version 3.2.0 for this fix.
I just noticed that the pom.xml from pmml-evaluator you shared shows a supported version range of [14.0, 20.0]
:
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>[14.0, 20.0]</version>
</dependency>
What you could do is exclude guava as a dependency in org.jpmml, i.e.:
<dependency>
<groupId>org.jpmml</groupId>
<artifactId>pmml-evaluator</artifactId>
<version>1.3.4</version>
<exclusions>
<exclusion>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
</exclusion>
</exclusions>
</dependency>
This should prevent guava 20.0 from being pulled in as a result of resolving dependencies for pmml-evaluator and guava 16.01 would instead be pulled in via transitive dependency of the java driver.