How to create a "NonBlockingConnectionPool "using a "java.sql.Connection" object already present ?

I tried creating a connectionpool using rxjava2-jdbc using a java.sql.Connection Object .

NonBlockingConnectionPool pool =
Pools.nonBlocking()
.maxPoolSize(Runtime.getRuntime().availableProcessors() * 5)
.connectionProvider(ConnectionProvider.from(connection))
.build();
But it strangely throws this NoSuchMethodError exception :

Caused by: java.lang.NoSuchMethodError: com.github.davidmoten.guavamini.Preconditions.checkNotNull(Ljava/lang/Object;Ljava/lang/String;)Ljava/lang/Object

**Scenario :-
I already have a java.sql.Connection Object , How to I use that to create a org.davidmoten.rx.jdbc.Database Object so that I can execute my SQL queries from ?**