com.google.common.collect.MapMaker @ Create java.util.concurrent.ConcurrentHashMap directly
com.google.common.collect.Maps#newConcurrentMap() @ Create java.util.concurrent.ConcurrentHashMap directly
com.google.common.util.concurrent.Futures#transform(com.google.common.util.concurrent.ListenableFuture, com.google.common.util.concurrent.AsyncFunction) @ Use io.druid.java.util.common.concurrent.ListenableFutures#transformAsync
com.google.common.collect.Iterators#emptyIterator() @ Use java.util.Collections#emptyIterator()
com.google.common.base.Charsets @ Use java.nio.charset.StandardCharsets instead